Oxytocin

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Oxytocin
Oxytocin with labels.png
Oxytocin-from-NMR-soln-3D-bs-17.png
Clinical data
Pronunciation /ˌɒksɪˈtsɪn/
ATC code
Physiological data
Source tissues Pituitary gland
Target tissuesWide spread
Receptors Oxytocin receptor
Antagonists Atosiban
Precursor Oxytocin/neurophysin I prepropeptide
Metabolism Liver and other oxytocinases
Legal status
Legal status
Pharmacokinetic data
Protein binding 30%
Metabolism Liver and other oxytocinases
Elimination half-life 1–6 min (IV)
~2 h (intranasal) [2] [3]
Excretion Biliary and kidney
Identifiers
  • 1-({(4R,7S,10S,13S,16S,19R)-19-amino-7-(2-amino-2-oxoethyl)-10-(3-amino-3-oxopropyl)-16-(4-hydroxybenzyl)-13-[(1S)-1-methylpropyl]-6,9,12,15,18-pentaoxo-1,2-dithia-5,8,11,14,17-pentaazacycloicosan-4-yl}carbonyl)-L-prolyl-L-leucylglycinamide
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard 100.000.045 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C43H66N12O12S2
Molar mass 1007.19 g·mol−1
3D model (JSmol)
  • CC[C@H](C)[C@@H]1NC(=O)[C@H](Cc2ccc(O)cc2)NC(=O)[C@@H](N)CSSC[C@H](NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CCC(N)=O)NC1=O)C(=O)N3CCC[C@H]3C(=O)N[C@@H](CC(C)C)C(=O)NCC(N)=O
  • InChI=1S/C43H66N12O12S2/c1-5-22(4)35-42(66)49-26(12-13-32(45)57)38(62)51-29(17-33(46)58)39(63)53-30(20-69-68-19-25(44)36(60)50-28(40(64)54-35)16-23-8-10-24(56)11-9-23)43(67)55-14-6-7-31(55)41(65)52-27(15-21(2)3)37(61)48-18-34(47)59/h8-11,21-22,25-31,35,56H,5-7,12-20,44H2,1-4H3,(H2,45,57)(H2,46,58)(H2,47,59)(H,48,61)(H,49,66)(H,50,60)(H,51,62)(H,52,65)(H,53,63)(H,54,64)/t22-,25-,26-,27-,28-,29-,30-,31-,35-/m0/s1 Yes check.svgY
  • Key:XNOPRXBHLZRZKH-DSZYJQQASA-N Yes check.svgY
   (verify)

Oxytocin is a peptide hormone and neuropeptide normally produced in the hypothalamus and released by the posterior pituitary. [4] Present in animals since early stages of evolution, in humans it plays roles in behavior that include social bonding, love, reproduction, childbirth, and the period after childbirth. [5] [6] [7] [8] Oxytocin is released into the bloodstream as a hormone in response to sexual activity and during childbirth. [9] [10] It is also available in pharmaceutical form. In either form, oxytocin stimulates uterine contractions to speed up the process of childbirth. In its natural form, it also plays a role in maternal bonding and milk production. [10] [11] Production and secretion of oxytocin is controlled by a positive feedback mechanism, where its initial release stimulates production and release of further oxytocin. For example, when oxytocin is released during a contraction of the uterus at the start of childbirth, this stimulates production and release of more oxytocin and an increase in the intensity and frequency of contractions. This process compounds in intensity and frequency and continues until the triggering activity ceases. A similar process takes place during lactation and during sexual activity.

Contents

Oxytocin is derived by enzymatic splitting from the peptide precursor encoded by the human OXT gene. The deduced structure of the active nonapeptide is:

Cys    Tyr    Ile    Gln    Asn   Cys   Pro    Leu    Gly   NH2, or CYIQNCPLG-NH2.

Etymology

The term "oxytocin" derives from the Greek "ὠκυτόκος" (ōkutókos), based on ὀξύς (oxús), meaning "sharp" or "swift", and τόκος (tókos), meaning "childbirth". [12] [13] The adjective form is "oxytocic", which refers to medicines which stimulate uterine contractions, to speed up the process of childbirth. Colloquially, it has been referred to as the "cuddle hormone" or the "moral molecule" which have been considered misnomers. [14]

History

The uterine-contracting properties of the principle that would later be named oxytocin were discovered by British pharmacologist Henry Hallett Dale in 1906, [15] [16] and its milk ejection property was described by Ott and Scott in 1910 [17] and by Schafer and Mackenzie in 1911. [18] In 1909, the first clinical use of oxytocin was performed by William Blair-Bell to induce childbirth in patients with complications. [19] [20]

By the 1920s, oxytocin and vasopressin had been isolated from pituitary tissue and given their current names. Oxytocin's molecular structure was determined in 1952. [21] In the early 1950s, American biochemist Vincent du Vigneaud found that oxytocin is made up of nine amino acids, and he identified its amino acid sequence, the first polypeptide hormone to be sequenced. [22] In 1953, du Vigneaud carried out the synthesis of oxytocin, the first polypeptide hormone to be synthesized. [23] [24] [25] Du Vigneaud was awarded the Nobel Prize in 1955 for his work. [26]

Further work on different synthetic routes for oxytocin, as well as the preparation of analogues of the hormone (e.g. 4-deamido-oxytocin) was performed in the following decade by Iphigenia Photaki. [27]

Biochemistry

OXT
Identifiers
Aliases OXT , OT, OT-NPI, OXT-NPI, oxytocin/neurophysin I prepropeptide
External IDs OMIM: 167050; MGI: 97453; HomoloGene: 55494; GeneCards: OXT; OMA:OXT - orthologs
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_000915

NM_011025

RefSeq (protein)

NP_000906

NP_035155

Location (UCSC) Chr 20: 3.07 – 3.07 Mb Chr 2: 130.42 – 130.42 Mb
PubMed search [30] [31]
Wikidata
View/Edit Human View/Edit Mouse

Estrogen has been found to increase the secretion of oxytocin and to increase the expression of its receptor, the oxytocin receptor, in the brain. [32] In women, a single dose of estradiol has been found to be sufficient to increase circulating oxytocin concentrations. [33]

Biosynthesis

Oxytocin and vasopressin are the only known hormones released by the human posterior pituitary gland to act at a distance. However, oxytocin neurons make other peptides, including corticotropin-releasing hormone (CRH) and dynorphin, for example, that act locally. The magnocellular neurons that make oxytocin are adjacent to magnocellular neurons that make vasopressin, and are similar in many respects.

The biosynthesis of the different forms of OT The biosynthesis of the different forms of OT.jpg
The biosynthesis of the different forms of OT

The oxytocin peptide is synthesized as an inactive precursor protein from the OXT gene. [34] [35] [36] This precursor protein also includes the oxytocin carrier protein neurophysin I. [37] The inactive precursor protein is progressively hydrolyzed into smaller fragments (one of which is neurophysin I) via a series of enzymes. The last hydrolysis that releases the active oxytocin nonapeptide is catalyzed by peptidylglycine alpha-amidating monooxygenase (PAM). [38]

The activity of the PAM enzyme system is dependent upon vitamin C (ascorbate), which is a necessary vitamin cofactor. By chance, sodium ascorbate by itself was found to stimulate the production of oxytocin from ovarian tissue over a range of concentrations in a dose-dependent manner. [39] Many of the same tissues (e.g. ovaries, testes, eyes, adrenals, placenta, thymus, pancreas) where PAM (and oxytocin by default) is found are also known to store higher concentrations of vitamin C. [40]

Oxytocin is known to be metabolized by the oxytocinase, leucyl/cystinyl aminopeptidase. [41] [42] Other oxytocinases are also known to exist. [41] [43] Amastatin, bestatin (ubenimex), leupeptin, and puromycin have been found to inhibit the enzymatic degradation of oxytocin, though they also inhibit the degradation of various other peptides, such as vasopressin, met-enkephalin, and dynorphin A. [43] [44] [45] [46]

Neural sources

In the hypothalamus, oxytocin is made in magnocellular neurosecretory cells of the supraoptic and paraventricular nuclei, [47] and is stored in Herring bodies at the axon terminals in the posterior pituitary. It is then released into the blood from the posterior lobe (neurohypophysis) of the pituitary gland. These axons (likely, but dendrites have not been ruled out) have collaterals that innervate neurons in the nucleus accumbens, a brain structure where oxytocin receptors are expressed. [48] The endocrine effects of hormonal oxytocin and the cognitive or behavioral effects of oxytocin neuropeptides are thought to be coordinated through its common release through these collaterals. [48] Oxytocin is also produced by some neurons in the paraventricular nucleus that project to other parts of the brain and to the spinal cord. [49] Depending on the species, oxytocin receptor-expressing cells are located in other areas, including the amygdala and bed nucleus of the stria terminalis.

In the pituitary gland, oxytocin is packaged in large, dense-core vesicles, where it is bound to neurophysin I as shown in the inset of the figure; neurophysin is a large peptide fragment of the larger precursor protein molecule from which oxytocin is derived by enzymatic cleavage.

Secretion of oxytocin from the neurosecretory nerve endings is regulated by the electrical activity of the oxytocin cells in the hypothalamus. These cells generate action potentials that propagate down axons to the nerve endings in the pituitary; the endings contain large numbers of oxytocin-containing vesicles, which are released by exocytosis when the nerve terminals are depolarised.

Non-neural sources

Endogenous oxytocin concentrations in the brain have been found to be as much as 1000-fold higher than peripheral levels. [50]

Outside the brain, oxytocin-containing cells have been identified in several diverse tissues, including in females in the corpus luteum [51] [52] and the placenta; [53] in males in the testicles' interstitial cells of Leydig; [54] and in both sexes in the retina, [55] the adrenal medulla, [56] the thymus [57] and the pancreas. [58] The finding of significant amounts of this classically "neurohypophysial" hormone outside the central nervous system raises many questions regarding its possible importance in these diverse tissues.

Male

The Leydig cells in some species have been shown to possess the biosynthetic machinery to manufacture testicular oxytocin de novo, to be specific, in rats (which can synthesize vitamin C endogenously), and in guinea pigs, which, like humans, require an exogenous source of vitamin C (ascorbate) in their diets. [59]

Female

Oxytocin is synthesized by corpora lutea of several species, including ruminants and primates. Along with estrogen, it is involved in inducing the endometrial synthesis of prostaglandin F to cause regression of the corpus luteum. [60]

Evolution

Virtually all vertebrates have an oxytocin-like nonapeptide hormone that supports reproductive functions and a vasopressin-like nonapeptide hormone involved in water regulation. The two genes are usually located close to each other (less than 15,000 bases apart) on the same chromosome, and are transcribed in opposite directions (however, in fugu, [61] the homologs are further apart and transcribed in the same direction). The two genes are believed to result from a gene duplication event; the ancestral gene is estimated to be about 500 million years old and is found in cyclostomata (modern members of the Agnatha). [62]

A 2023 study found that zebrafish utilize oxytocin in reaction to the fear of other fish. It found that zebrafish that have had oxytocin production removed by gene editing cannot respond to the fear of other fish. When oxytocin is injected back into the fish, they react again in a way that suggests they may have empathy in regards to this emotion. Furthermore, because the same regions of the brain are involved as in mammals, the study suggests oxytocin-based empathy may have evolved from a common ancestor many millions of years ago. [63]

Biological function

Oxytocin has peripheral (hormonal) actions, and also has actions in the brain. Its actions are mediated by specific oxytocin receptors. The oxytocin receptor is a G-protein-coupled receptor, OT-R, which requires magnesium and cholesterol and is expressed in myometrial cells. [64] It belongs to the rhodopsin-type (class I) group of G-protein-coupled receptors. [62]

Studies have looked at oxytocin's role in various behaviors, including orgasm, social recognition, pair bonding, anxiety, in-group bias, situational lack of honesty, autism, and maternal behaviors. [16] Oxytocin is believed to have a significant role in social learning. There are indicators that oxytocin may help to decrease noise in the brain's auditory system, increase perception of social cues and support more targeted social behavior. It may also enhance reward responses. However, its effects may be influenced by context, such as the presence of familiar or unfamiliar individuals. [65] [66]

In addition to its oxytocin receptor agonism, oxytocin has been found to act as a positive allosteric modulator (PAM) of the μ- and κ-opioid receptors and this may be involved in its analgesic effects. [67] [68] [69] [70] [71] [72]

Physiological

The peripheral actions of oxytocin mainly reflect secretion from the pituitary gland. The behavioral effects of oxytocin are thought to reflect release from centrally projecting oxytocin neurons, different from those that project to the pituitary gland, or that are collaterals from them. [48] Oxytocin receptors are expressed by neurons in many parts of the brain and spinal cord, including the amygdala, ventromedial hypothalamus, septum, nucleus accumbens, and brainstem, although the distribution differs markedly between species. [62] Furthermore, the distribution of these receptors changes during development and has been observed to change after parturition in the montane vole. [62]

In a study measuring oxytocin serum levels in women before and after sexual stimulation, the author suggests it serves an important role in sexual arousal. This study found genital tract stimulation resulted in increased oxytocin immediately after orgasm. [79] Another study reported increases of oxytocin during sexual arousal could be in response to nipple/areola, genital, and/or genital tract stimulation as confirmed in other mammals. [80] Murphy et al. (1987), studying men, found that plasma oxytocin levels remain unchanged during sexual arousal, but that levels increase sharply after ejaculation, returning to baseline levels within 30 minutes. In contrast, vasopressin was increased during arousal but returned to baseline at the time of ejaculation. The study concludes that (in males) vasopressin is secreted during arousal, while oxytocin is only secreted after ejaculation. [81] A more recent study of men found an increase in plasma oxytocin immediately after orgasm, but only in a portion of their sample that did not reach statistical significance. The authors noted these changes "may simply reflect contractile properties on reproductive tissue". [82]

Psychological

Bonding

In the prairie vole, oxytocin released into the brain of the female during sexual activity is important for forming a pair bond with her sexual partner. Vasopressin appears to have a similar effect in males. [99] Oxytocin has a role in social behaviors in many species, so it likely also does in humans. In a 2003 study, both humans and dog oxytocin levels in the blood rose after a five to 24 minute petting session. This possibly plays a role in the emotional bonding between humans and dogs. [100]

  • Maternal behavior: Female rats given oxytocin antagonists after giving birth do not exhibit typical maternal behavior. [101] By contrast, virgin female sheep show maternal behavior toward foreign lambs upon cerebrospinal fluid infusion of oxytocin, which they would not do otherwise. [102] Oxytocin is involved in the initiation of human maternal behavior, not its maintenance; for example, it is higher in mothers after they interact with unfamiliar children rather than their own. [103]
  • Human ingroup bonding: Oxytocin can increase positive attitudes, such as bonding, toward individuals classified as "in-group" members, whereas other individuals become classified as "out-group" members. Oxytocin has also been implicated in lying when lying would prove beneficial to other in-group members. In a study where such a relationship was examined, it was found that when individuals were administered oxytocin, rates of dishonesty in the participants' responses increased for their in-group members when a beneficial outcome for their group was expected. [104] Both of these examples show the tendency of individuals to act in ways that benefit those considered to be members of their social group, or in-group.
  • Decreased oxytocin & receptor expression has been associated with aggressive behavior in aggressive-impulsive disorders. [105]

Oxytocin is not only correlated with the preferences of individuals to associate with members of their own group, but it is also evident during conflicts between members of different groups. During conflict, individuals receiving nasally administered oxytocin demonstrate more frequent defense-motivated responses toward in-group members than out-group members. Further, oxytocin was correlated with participant desire to protect vulnerable in-group members, despite that individual's attachment to the conflict. [106] Similarly, it has been demonstrated that when oxytocin is administered, individuals alter their subjective preferences in order to align with in-group ideals over out-group ideals. [107] These studies demonstrate that oxytocin is associated with intergroup dynamics. Further, oxytocin influences the responses of individuals in a particular group to those of another group. The in-group bias is evident in smaller groups; however, it can also be extended to groups as large as one's entire country leading toward a tendency of strong national zeal. A study done in the Netherlands showed that oxytocin increased the in-group favoritism of their nation while decreasing acceptance of members of other ethnicities and foreigners. [108] People also show more affection for their country's flag while remaining indifferent to other cultural objects when exposed to oxytocin. [109] It has thus been hypothesized that this hormone may be a factor in xenophobic tendencies secondary to this effect. Thus, oxytocin appears to affect individuals at an international level where the in-group becomes a specific "home" country and the out-group grows to include all other countries.

Drugs

Fear and anxiety

Oxytocin is typically remembered for the effect it has on prosocial behaviors, such as its role in facilitating trust and attachment between individuals. [115] [ qualify evidence ] However, oxytocin has a more complex role than solely enhancing prosocial behaviors. There is consensus that oxytocin modulates fear and anxiety; that is, it does not directly elicit fear or anxiety. [116] Two dominant theories explain the role of oxytocin in fear and anxiety. One theory states that oxytocin increases approach/avoidance to certain social stimuli and the second theory states that oxytocin increases the salience of certain social stimuli, causing animals (including humans) to pay closer attention to socially relevant stimuli. [117] [118] [119]

Nasally administered oxytocin has been reported to reduce fear, possibly by inhibiting the amygdala (which is thought to be responsible for fear responses). [120] Indeed, studies in rodents have shown oxytocin can efficiently inhibit fear responses by activating an inhibitory circuit within the amygdala. [121] [122] Some researchers have argued oxytocin has a general enhancing effect on all social emotions, since intranasal administration of oxytocin also increases envy and Schadenfreude . [123] Individuals who receive an intranasal dose of oxytocin identify facial expressions of disgust more quickly than individuals who do not receive oxytocin. [117] [ qualify evidence ] Facial expressions of disgust are evolutionarily linked to the idea of contagion. Thus, oxytocin increases the salience of cues that imply contamination, which leads to a faster response because these cues are especially relevant for survival. In another study, after administration of oxytocin, individuals displayed an enhanced ability to recognize expressions of fear compared to the individuals who received the placebo. [124] Oxytocin modulates fear responses by enhancing the maintenance of social memories. Rats who are genetically modified to have a surplus of oxytocin receptors display a greater fear response to a previously conditioned stressor. Oxytocin enhances the aversive social memory, leading the rat to display a greater fear response when the aversive stimulus is encountered again. [116]

Mood and depression

Oxytocin produces antidepressant-like effects in animal models of depression, [125] and a deficit of it may be involved in the pathophysiology of depression in humans. [126] The antidepressant-like effects of oxytocin are not blocked by a selective antagonist of the oxytocin receptor, suggesting that these effects are not mediated by the oxytocin receptor. [33] In accordance, unlike oxytocin, the selective non-peptide oxytocin receptor agonist WAY-267,464 does not produce antidepressant-like effects, at least in the tail suspension test. [127] In contrast to WAY-267,464, carbetocin, a close analogue of oxytocin and peptide oxytocin receptor agonist, notably does produce antidepressant-like effects in animals. [127] As such, the antidepressant-like effects of oxytocin may be mediated by modulation of a different target, perhaps the vasopressin V1A receptor where oxytocin is known to weakly bind as an agonist. [128] [129]

Oxytocin mediates the antidepressant-like effects of sexual activity. [130] [131] A drug for sexual dysfunction, sildenafil enhances electrically evoked oxytocin release from the pituitary gland. [132] In accordance, it may have promise as an antidepressant. [125] [133]

Sex differences

It has been shown that oxytocin differentially affects males and females. Females who are administered oxytocin are overall faster in responding to socially relevant stimuli than males who received oxytocin. [117] [134] Additionally, after the administration of oxytocin, females show increased amygdala activity in response to threatening scenes; however, males do not show increased amygdala activation. This phenomenon can be explained by looking at the role of gonadal hormones, specifically estrogen, which modulate the enhanced threat processing seen in females. Estrogen has been shown to stimulate the release of oxytocin from the hypothalamus and promote receptor binding in the amygdala. [134]

It has also been shown that testosterone directly suppresses oxytocin in mice. [135] This has been hypothesized to have evolutionary significance. With oxytocin suppressed, activities such as hunting and attacking invaders would be less mentally difficult as oxytocin is strongly associated with empathy. [136]

Social

Because oxytocin plays a role in social bonding, maternal behaviors and emotional connections between people, it is also informally referred to as the "love hormone". [137] This term is not a medical or scientific name but is often used to describe oxytocin's effects on human behavior and emotions.

  • Affecting generosity by increasing empathy during perspective taking: In a neuroeconomics experiment, intranasal oxytocin increased generosity in the Ultimatum Game by 80%, but had no effect in the Dictator Game that measures altruism. Perspective-taking is not required in the Dictator Game, but the researchers in this experiment explicitly induced perspective-taking in the Ultimatum Game by not identifying to participants into which role they would be placed. [138] Serious methodological questions have arisen, however, with regard to the role of oxytocin in trust and generosity. [139] Empathy in healthy males has been shown to be increased after intranasal oxytocin [136] [140] This is most likely due to the effect of oxytocin in enhancing eye gaze. [141] There is some discussion about which aspect of empathy oxytocin might alter – for example, cognitive vs. emotional empathy. [142] While studying wild chimpanzees, it was noted that after a chimpanzee shared food with a non-kin related chimpanzee, the subjects' levels of oxytocin increased, as measured through their urine. In comparison to other cooperative activities between chimpanzees that were monitored including grooming, food sharing generated higher levels of oxytocin. This comparatively higher level of oxytocin after food sharing parallels the increased level of oxytocin in nursing mothers, sharing nutrients with their kin. [143]
  • Trust is increased by oxytocin. [144] [145] [146] [147] Study found that with the oxytocin nasal spray, people place more trust to strangers in handling their money. [144] [148] Disclosure of emotional events is a sign of trust in humans. When recounting a negative event, humans who receive intranasal oxytocin share more emotional details and stories with more emotional significance. [146] Humans also find faces more trustworthy after receiving intranasal oxytocin. In a study, participants who received intranasal oxytocin viewed photographs of human faces with neutral expressions and found them to be more trustworthy than those who did not receive oxytocin. [145] This may be because oxytocin reduces the fear of social betrayal in humans. [149] Even after experiencing social alienation by being excluded from a conversation, humans who received oxytocin scored higher in trust on the Revised NEO Personality Inventory. [147] Moreover, in a risky investment game, experimental subjects given nasally administered oxytocin displayed "the highest level of trust" twice as often as the control group. Subjects who were told they were interacting with a computer showed no such reaction, leading to the conclusion that oxytocin was not merely affecting risk aversion. [150] When there is a reason to be distrustful, such as experiencing betrayal, differing reactions are associated with oxytocin receptor gene (OXTR) differences. Those with the CT haplotype [ clarification needed ] experience a stronger reaction, in the form of anger, to betrayal. [151]
  • Romantic attachment: In some studies, high levels of plasma oxytocin have been correlated with romantic attachment. For example, if a couple is separated for a long period of time, anxiety can increase due to the lack of physical affection. Oxytocin may aid romantically attached couples by increasing feelings of anxiety during separation. [152]
  • Group-serving dishonesty/deception: In a carefully controlled study exploring the biological roots of immoral behavior, oxytocin was shown to promote dishonesty when the outcome favored the group to which an individual belonged instead of just the individual. [153]
  • Oxytocin affects social distance between adult males and females, and may be responsible at least in part for romantic attraction and subsequent monogamous pair bonding. An oxytocin nasal spray caused men in a monogamous relationship, but not single men, to increase the distance between themselves and an attractive woman during a first encounter by 10 to 15 centimeters. The researchers suggested that oxytocin may help promote fidelity within monogamous relationships. [154] For this reason, it is sometimes referred to as the "bonding hormone". There is some evidence that oxytocin promotes ethnocentric behavior, incorporating the trust and empathy of in-groups with their suspicion and rejection of outsiders. [108] Furthermore, genetic differences in the oxytocin receptor gene (OXTR) have been associated with maladaptive social traits such as aggressive behavior. [155]
  • Social behavior [108] [156] and wound healing: Oxytocin is also thought to modulate inflammation by decreasing certain cytokines. [157] Thus, the increased release in oxytocin following positive social interactions has the potential to improve wound healing. A study by Marazziti and colleagues used heterosexual couples to investigate this possibility. They found increases in plasma oxytocin following a social interaction were correlated with faster wound healing. They hypothesized this was due to oxytocin reducing inflammation, thus allowing the wound to heal more quickly. This study provides preliminary evidence that positive social interactions may directly influence aspects of health. [158]
  • According to a study published in 2014, silencing of oxytocin receptor interneurons in the medial prefrontal cortex (mPFC) of female mice resulted in loss of social interest in male mice during the sexually receptive phase of the estrous cycle. [159] Oxytocin evokes feelings of contentment, reductions in anxiety, and feelings of calmness and security when in the company of the mate. [152] This suggests oxytocin may be important for the inhibition of the brain regions associated with behavioral control, fear, and anxiety, thus allowing orgasm to occur. Research has also demonstrated that oxytocin can decrease anxiety and protect against stress, particularly in combination with social support. [160] [161] It is found that endocannabinoid signaling mediates oxytocin-driven social reward. [162] During a 2008 study, a lack of oxytocin in mice was associated with abnormalities in emotional behavior. [163] Another study conducted in 2014 saw similar results with a variation in the oxytocin receptor connected with dopamine transport and how levels of oxytocin are dependent on the levels of dopamine transporter levels. [164] One study explored the effects of low levels of oxytocin and the other on possible explanation of what affects oxytocin receptors. As a lack of social skills and proper emotional behavior are common signs of Autism, low levels of oxytocin could become a new sign for individuals that fall into the Autism Spectrum.

Chemistry

Oxytocin (ball-and-stick) bound to its carrier protein neurophysin (ribbons) Oxytocin-neurophysin.png
Oxytocin (ball-and-stick) bound to its carrier protein neurophysin (ribbons)

Oxytocin is a peptide of nine amino acids (a nonapeptide) in the sequence cysteine-tyrosine-isoleucine-glutamine-asparagine-cysteine-proline-leucine-glycine-amide (Cys    Tyr    Ile    Gln    Asn   Cys   Pro    Leu    Gly   NH2, or CYIQNCPLG-NH2); its C-terminus has been converted to a primary amide and a disulfide bridge joins the cysteine moieties. [165] Oxytocin has a molecular mass of 1007  Da, and one international unit (IU) of oxytocin is the equivalent of 1.68  μg of pure peptide. [166]

While the structure of oxytocin is highly conserved in placental mammals, a novel structure of oxytocin was reported in 2011 in marmosets, tamarins, and other new world primates. Genomic sequencing of the gene for oxytocin revealed a single in-frame mutation (thymine for cytosine) which results in a single amino acid substitution at the 8-position (proline for leucine). [167] Since this original Lee et al. paper, two other laboratories have confirmed Pro8-OT and documented additional oxytocin structural variants in this primate taxon. Vargas-Pinilla et al. sequenced the coding regions of the OXT gene in other genera in new world primates and identified the following variants in addition to Leu8- and Pro8-OT: Ala8-OT, Thr8-OT, and Val3/Pro8-OT. [168] Ren et al. identified a variant further, Phe2-OT in howler monkeys. [169]

Recent advances in analytical instrumental techniques highlighted the importance of liquid chromatography (LC) coupled with mass spectrometry (MS) for measuring oxytocin levels in various samples derived from biological sources. Most of these studies optimized the oxytocin quantification in electrospray ionization (ESI) positive mode, using [M+H]+ as the parent ion at mass-to-charge ratio (m/z) 1007.4 and the fragment ions as diagnostic peaks at m/z 991.0, [170] m/z 723.2 [171] and m/z 504.2. [172] These important ion selections paved the way for the development of current methods of oxytocin quantification using MS instrumentation.

The structure of oxytocin is very similar to that of vasopressin. Both are nonapeptides with a single disulfide bridge, differing only by two substitutions in the amino acid sequence (differences from oxytocin bolded for clarity): Cys  Tyr   Phe   Gln  Asn  Cys  Pro   Arg   Gly  NH2. [165] Oxytocin and vasopressin were isolated and their total synthesis reported in 1954, [173] work for which Vincent du Vigneaud was awarded the 1955 Nobel Prize in Chemistry with the citation: "for his work on biochemically important sulphur compounds, especially for the first synthesis of a polypeptide hormone." [174]

Oxytocin and vasopressin are the only known hormones released by the human posterior pituitary gland to act at a distance. However, oxytocin neurons make other peptides, including corticotropin-releasing hormone and dynorphin, for example, that act locally. The magnocellular neurosecretory cells that make oxytocin are adjacent to magnocellular neurosecretory cells that make vasopressin. These are large neuroendocrine neurons which are excitable and can generate action potentials. [175]

"Oxytocin" is the name of the fifth song on Billie Eilish's second album Happier Than Ever .

Oxytocin is mentioned in the first lyric of Post Malone's song Chemical.

In the novel The Fireman by Joe Hill, the hormone plays a role in neutralizing the danger posed by an infectious spore that causes a condition known as Dragonscale. If the spore enters an oxytocin-rich environment, it will enter a dormant state instead of causing its host to undergo spontaneous human combustion.

The formula for oxytocin is displayed as written on the fingers of Nina Zilli and appears in the opening shot of her video for "Sola".

In medicine

Small-molecule oxytocin receptor agonists like LIT-001 may prove to be useful in the treatment of social deficits, for instance in autism. [176] [177] [178]

See also

Related Research Articles

<span class="mw-page-title-main">Hypothalamus</span> Area of the brain below the thalamus

The hypothalamus is a small part of the vertebrate brain that contains a number of nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamus is located below the thalamus and is part of the limbic system. It forms the basal part of the diencephalon. All vertebrate brains contain a hypothalamus. In humans, it is about the size of an almond.

<span class="mw-page-title-main">Hypothalamic–pituitary–adrenal axis</span> Set of physiological feedback interactions

The hypothalamic–pituitary–adrenal axis is a complex set of direct influences and feedback interactions among three components: the hypothalamus, the pituitary gland, and the adrenal glands. These organs and their interactions constitute the HPS axis.

<span class="mw-page-title-main">Vasopressin</span> Mammalian hormone released from the pituitary gland

Human vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP) or argipressin, is a hormone synthesized from the AVP gene as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then travels down the axon terminating in the posterior pituitary, and is released from vesicles into the circulation in response to extracellular fluid hypertonicity (hyperosmolality). AVP has two primary functions. First, it increases the amount of solute-free water reabsorbed back into the circulation from the filtrate in the kidney tubules of the nephrons. Second, AVP constricts arterioles, which increases peripheral vascular resistance and raises arterial blood pressure.

<span class="mw-page-title-main">Empathogen</span> Class of psychoactive drugs that produce empathic experiences

Empathogens or entactogens are a class of psychoactive drugs that induce the production of experiences of emotional communion, oneness, relatedness, emotional openness—that is, empathy or sympathy—as particularly observed and reported for experiences with 3,4-methylenedioxymethamphetamine (MDMA). This class of drug is distinguished from the classes of hallucinogen or psychedelic, and amphetamine or stimulants. Major members of this class include MDMA, MDA, MDEA, MDOH, MBDB, 5-APB, 5-MAPB, 6-APB, 6-MAPB, methylone, mephedrone, GHB, αMT, and αET, MDAI among others. Most entactogens are phenethylamines and amphetamines, although several, such as αMT and αET, are tryptamines. When referring to MDMA and its counterparts, the term MDxx is often used. Entactogens are sometimes incorrectly referred to as hallucinogens or stimulants, although many entactogens such as ecstasy exhibit psychedelic or stimulant properties as well.

<span class="mw-page-title-main">Supraoptic nucleus</span> ADH secreting nucleus of the hypothalamus.

The supraoptic nucleus (SON) is a nucleus of magnocellular neurosecretory cells in the hypothalamus of the mammalian brain. The nucleus is situated at the base of the brain, adjacent to the optic chiasm. In humans, the SON contains about 3,000 neurons.

<span class="mw-page-title-main">Paraventricular nucleus of hypothalamus</span>

The paraventricular nucleus of hypothalamus is a nucleus in the hypothalamus, that lies next to the third ventricle. Many of its neurons project to the posterior pituitary where they secrete oxytocin, and a smaller amount of vasopressin. Other secretions are corticotropin-releasing hormone (CRH) and thyrotropin-releasing hormone (TRH). CRH and TRH are secreted into the hypophyseal portal system, and target different neurons in the anterior pituitary. Dysfunctions of the PVN can cause hypersomnia in mice. In humans, the dysfunction of the PVN and the other nuclei around it can lead to drowsiness for up to 20 hours per day. The PVN is thought to mediate many diverse functions through different hormones, including osmoregulation, appetite, wakefulness, and the response of the body to stress.

Magnocellular neurosecretory cells are large neuroendocrine cells within the supraoptic nucleus and paraventricular nucleus of the hypothalamus. They are also found in smaller numbers in accessory cell groups between these two nuclei, the largest one being the circular nucleus. There are two types of magnocellular neurosecretory cells, oxytocin-producing cells and vasopressin-producing cells, but a small number can produce both hormones. These cells are neuroendocrine neurons, are electrically excitable, and generate action potentials in response to afferent stimulation. Vasopressin is produced from the vasopressin-producing cells via the AVP gene, a molecular output of circadian pathways.

<span class="mw-page-title-main">Gonadotropin-releasing hormone</span> Mammalian protein found in Homo sapiens

Gonadotropin-releasing hormone (GnRH) is a releasing hormone responsible for the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary. GnRH is a tropic peptide hormone synthesized and released from GnRH neurons within the hypothalamus. The peptide belongs to gonadotropin-releasing hormone family. It constitutes the initial step in the hypothalamic–pituitary–gonadal axis.

<span class="mw-page-title-main">Neuropeptide</span> Peptides released by neurons as intercellular messengers

Neuropeptides are chemical messengers made up of small chains of amino acids that are synthesized and released by neurons. Neuropeptides typically bind to G protein-coupled receptors (GPCRs) to modulate neural activity and other tissues like the gut, muscles, and heart.

<span class="mw-page-title-main">Vasoactive intestinal peptide</span> Hormone that affects blood pressure / heart rate

Vasoactive intestinal peptide, also known as vasoactive intestinal polypeptide or VIP, is a peptide hormone that is vasoactive in the intestine. VIP is a peptide of 28 amino acid residues that belongs to a glucagon/secretin superfamily, the ligand of class II G protein–coupled receptors. VIP is produced in many tissues of vertebrates including the gut, pancreas, cortex, and suprachiasmatic nuclei of the hypothalamus in the brain. VIP stimulates contractility in the heart, causes vasodilation, increases glycogenolysis, lowers arterial blood pressure and relaxes the smooth muscle of trachea, stomach and gallbladder. In humans, the vasoactive intestinal peptide is encoded by the VIP gene.

Neuroendocrinology is the branch of biology which studies the interaction between the nervous system and the endocrine system; i.e. how the brain regulates the hormonal activity in the body. The nervous and endocrine systems often act together in a process called neuroendocrine integration, to regulate the physiological processes of the human body. Neuroendocrinology arose from the recognition that the brain, especially the hypothalamus, controls secretion of pituitary gland hormones, and has subsequently expanded to investigate numerous interconnections of the endocrine and nervous systems.

<span class="mw-page-title-main">Vasopressin receptor 1A</span> Protein-coding gene in the species Homo sapiens

Vasopressin receptor 1A (V1AR), or arginine vasopressin receptor 1A is one of the three major receptor types for vasopressin, and is present throughout the brain, as well as in the periphery in the liver, kidney, and vasculature.

<span class="mw-page-title-main">Vasopressin receptor 1B</span> Protein-coding gene in the species Homo sapiens

Vasopressin V1b receptor (V1BR) also known as vasopressin 3 receptor (VPR3) or antidiuretic hormone receptor 1B is a protein that in humans is encoded by the AVPR1B gene.

<span class="mw-page-title-main">Vasotocin</span> Chemical compound

Vasotocin is an oligopeptide homologous to oxytocin and vasopressin found in all non-mammalian vertebrates and possibly in mammals during the fetal stage of development. Arginine vasotocin (AVT), a hormone produced by neurosecretory cells within the posterior pituitary gland (neurohypophysis) of the brain, is a major endocrine regulator of water balance and osmotic homoeostasis and is involved in social and sexual behavior in non-mammalian vertebrates. In mammals, it appears to have biological properties similar to those of oxytocin and vasopressin. It has been found to have effects on the regulation of REM sleep. Evidence for the existence of endogenous vasotocin in mammals is limited and no mammalian gene encoding vasotocin has been confirmed.

<span class="mw-page-title-main">Oxytocin receptor</span> Genes on human chromosome 3

The oxytocin receptor, also known as OXTR, is a protein which functions as receptor for the hormone and neurotransmitter oxytocin. In humans, the oxytocin receptor is encoded by the OXTR gene which has been localized to human chromosome 3p25.

A serenic, or anti-aggressive drug, is a type of drug which reduces the capacity for aggression.

<span class="mw-page-title-main">Parental brain</span>

Parental experience, as well as changing hormone levels during pregnancy and postpartum, cause changes in the parental brain. Displaying maternal sensitivity towards infant cues, processing those cues and being motivated to engage socially with her infant and attend to the infant's needs in any context could be described as mothering behavior and is regulated by many systems in the maternal brain. Research has shown that hormones such as oxytocin, prolactin, estradiol and progesterone are essential for the onset and the maintenance of maternal behavior in rats, and other mammals as well. Mothering behavior has also been classified within the basic drives.

Endocrinology of parenting has been the subject of considerable study with focus both on human females and males and on females and males of other mammalian species. Parenting as an adaptive problem in mammals involves specific endocrine signals that were naturally selected to respond to infant cues and environmental inputs. Infants across species produce a number of cues to inform caregivers of their needs. These include visual cues, like facial characteristics, or in some species smiling, auditory cues, such as vocalizations, olfactory cues, and tactile stimulation. A commonly mentioned hormone in parenting is oxytocin, however many other hormones relay key information that results in variations in behavior. These include estrogen, progesterone, prolactin, cortisol, and testosterone. While hormones are not necessary for the expression of maternal behavior, they may influence it.

<span class="mw-page-title-main">Oxytocin (medication)</span> Medication made from the peptide oxytocin

Synthetic oxytocin, sold under the brand name Pitocin among others, is a medication made from the peptide oxytocin. As a medication, it is used to cause contraction of the uterus to start labor, increase the speed of labor, and to stop bleeding following delivery. For this purpose, it is given by injection either into a muscle or into a vein.

<span class="mw-page-title-main">AVP gene</span> Gene

The arginine vasopressin (AVP) gene is a gene whose product is proteolytically cleaved to produce vasopressin, neurophysin II, and a glycoprotein called copeptin. AVP and other AVP-like peptides are found in mammals, as well as mollusks, arthropods, nematodes, and other invertebrate species. In humans, AVP is present on chromosome 20 and plays a role in homeostatic regulation. The products of AVP have many functions that include vasoconstriction, regulating the balance of water in the body, and regulating responses to stress. Expression of AVP is regulated by the transcription translation feedback loop (TTFL), which is an important part of the circadian system that controls the expression of clock genes. AVP has important implications in the medical field as its products have significant roles throughout body.

References

  1. "FDA-sourced list of all drugs with black box warnings (Use Download Full Results and View Query links.)". nctr-crs.fda.gov. FDA . Retrieved 22 Oct 2023.
  2. Weisman O, Zagoory-Sharon O, Feldman R (September 2012). "Intranasal oxytocin administration is reflected in human saliva". Psychoneuroendocrinology. 37 (9): 1582–1586. doi:10.1016/j.psyneuen.2012.02.014. PMID   22436536. S2CID   25253083.
  3. Huffmeijer R, Alink LR, Tops M, Grewen KM, Light KC, Bakermans-Kranenburg MJ, et al. (2012). "Salivary levels of oxytocin remain elevated for more than two hours after intranasal oxytocin administration". Neuro Endocrinology Letters. 33 (1): 21–25. PMID   22467107.
  4. Gray's Anatomy: The Anatomical Basis of Clinical Practice (41 ed.). Elsevier Health Sciences. 2015. p. 358. ISBN   978-0-7020-6851-5.
  5. Audunsdottir K, Quintana DS (2022-01-25). "Oxytocin's dynamic role across the lifespan". Aging Brain. 2: 100028. doi: 10.1016/j.nbas.2021.100028 . ISSN   2589-9589. PMC   9997153 . PMID   36908876. S2CID   246314607.
  6. Leng G, Leng RI (November 2021). "Oxytocin: A citation network analysis of 10 000 papers". Journal of Neuroendocrinology. 33 (11): e13014. doi: 10.1111/jne.13014 . hdl: 20.500.11820/d2bdf31e-1d12-4abf-80a3-659a7e31a9f7 . PMID   34328668. S2CID   236516186.
  7. Francis DD, Young LJ, Meaney MJ, Insel TR (May 2002). "Naturally occurring differences in maternal care are associated with the expression of oxytocin and vasopressin (V1a) receptors: gender differences". Journal of Neuroendocrinology. 14 (5): 349–53. doi:10.1046/j.0007-1331.2002.00776.x. PMID   12000539. S2CID   16005801.
  8. Gainer H, Fields RL, House SB (October 2001). "Vasopressin gene expression: experimental models and strategies". Experimental Neurology. 171 (2): 190–9. doi:10.1006/exnr.2001.7769. PMID   11573971. S2CID   25718623.
  9. Rogers K (7 July 2023). "Oxytocin". Encyclopædia Britannica.
  10. 1 2 Chiras DD (2012). Human Biology (7th ed.). Sudbury, MA: Jones & Bartlett Learning. p. 262. ISBN   978-0-7637-8345-7.
  11. Human Evolutionary Biology. Cambridge University Press. 2010. p. 282. ISBN   978-1-139-78900-4.
  12. "oxytocic - Wiktionary". en.wiktionary.org. 14 October 2019. Retrieved 2021-08-05.
  13. "oxytocin - Wiktionary". en.wiktionary.org. 15 July 2021. Retrieved 2021-08-05.
  14. Yong E (13 November 2015). "The weak science behind the wrongly named moral molecule". The Atlantic. Retrieved 18 September 2023.
  15. Dale HH (May 1906). "On some physiological actions of ergot". The Journal of Physiology. 34 (3): 163–206. doi:10.1113/jphysiol.1906.sp001148. PMC   1465771 . PMID   16992821.
  16. 1 2 Lee HJ, Macbeth AH, Pagani JH, Young WS (June 2009). "Oxytocin: the great facilitator of life". Progress in Neurobiology. 88 (2): 127–151. doi:10.1016/j.pneurobio.2009.04.001. PMC   2689929 . PMID   19482229.
  17. Ott I, Scott JC (1910). "The action of infundibulin upon the mammary secretion". Experimental Biology and Medicine. 8 (2): 48–49. doi:10.3181/00379727-8-27. S2CID   87519246.
  18. Schafer EA, Mackenzie K (July 1911). "The Action of Animal Extracts on Milk Secretion". Proceedings of the Royal Society B. 84 (568): 16–22. Bibcode:1911RSPSB..84...16S. doi: 10.1098/rspb.1911.0042 .
  19. Bell WB (December 1909). "The Pituitary Body and the Therapeutic Value of the Infundibular Extract in Shock, Uterine Atony, and Intestinal Paresis". British Medical Journal. 2 (2553): 1609–1613. doi:10.1136/bmj.2.2553.1609. PMC   2321437 . PMID   20764780.
  20. Stone ML (January 1950). "The intravenous use of dilute pituitrin for the induction and stimulation of labor". American Journal of Obstetrics and Gynecology. 59 (1): 49–57. doi:10.1016/0002-9378(50)90340-1. PMID   15399625.
  21. Corey EJ (2012). "Oxytocin". Molecules and Medicine. John Wiley & Sons. ISBN   978-1-118-36173-3.
  22. Du Vigneaud V, Ressler C, Trippett S (December 1953). "The sequence of amino acids in oxytocin, with a proposal for the structure of oxytocin". The Journal of Biological Chemistry. 205 (2): 949–957. doi: 10.1016/S0021-9258(18)49238-1 . PMID   13129273.
  23. Lee HJ, Macbeth AH, Pagani JH, Young WS (June 2009). "Oxytocin: the great facilitator of life". Progress in Neurobiology. 88 (2). US National Library of Medicine National Institutes of Health: 127–151. doi:10.1016/j.pneurobio.2009.04.001. PMC   2689929 . PMID   19482229.
  24. du Vigneaud V, Ressler C, Swan JM, Roberts CW, Katsoyannis PG, Gordon S (1953). "The synthesis of an octapeptide amide with the hormonal activity of oxytocin". J. Am. Chem. Soc. 75 (19): 4879–80. doi:10.1021/ja01115a553.
  25. du Vigneaud V, Ressler C, Swan JM, Roberts CW, Katsoyannis PG (1954). "The Synthesis of Oxytocin1". Journal of the American Chemical Society. 76 (12): 3115–21. doi:10.1021/ja01641a004.
  26. Du Vigneaud V (June 1956). "Trail of sulfur research: from insulin to oxytocin". Science. 123 (3205): 967–974. Bibcode:1956Sci...123..967D. doi:10.1126/science.123.3205.967. PMID   13324123.
  27. Iphigenia Vourvidou-Photaki: Biographical Statement and Scientific Work (PDF) (in Greek). Athens: F. Konstantinidis & K. Mihalas. 1968. pp. 5–42. Archived from the original (PDF) on 2021-04-12. Retrieved 2021-04-13.
  28. 1 2 3 GRCh38: Ensembl release 89: ENSG00000101405 Ensembl, May 2017
  29. 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000027301 Ensembl, May 2017
  30. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  31. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  32. Goldstein I, Meston CM, Davis S, Traish A (17 November 2005). Women's Sexual Function and Dysfunction: Study, Diagnosis and Treatment. CRC Press. pp. 205–. ISBN   978-1-84214-263-9.
  33. 1 2 Acevedo-Rodriguez A, Mani SK, Handa RJ (2015). "Oxytocin and Estrogen Receptor β in the Brain: An Overview". Frontiers in Endocrinology. 6: 160. doi: 10.3389/fendo.2015.00160 . PMC   4606117 . PMID   26528239.
  34. Sausville E, Carney D, Battey J (August 1985). "The human vasopressin gene is linked to the oxytocin gene and is selectively expressed in a cultured lung cancer cell line". The Journal of Biological Chemistry. 260 (18): 10236–10241. doi: 10.1016/S0021-9258(17)39236-0 . PMID   2991279.
  35. Repaske DR, Phillips JA, Kirby LT, Tze WJ, D'Ercole AJ, Battey J (March 1990). "Molecular analysis of autosomal dominant neurohypophyseal diabetes insipidus". The Journal of Clinical Endocrinology and Metabolism. 70 (3): 752–757. doi:10.1210/jcem-70-3-752. PMID   1968469.
  36. Summar ML, Phillips JA, Battey J, Castiglione CM, Kidd KK, Maness KJ, et al. (June 1990). "Linkage relationships of human arginine vasopressin-neurophysin-II and oxytocin-neurophysin-I to prodynorphin and other loci on chromosome 20". Molecular Endocrinology. 4 (6): 947–950. doi: 10.1210/mend-4-6-947 . PMID   1978246.
  37. Brownstein MJ, Russell JT, Gainer H (January 1980). "Synthesis, transport, and release of posterior pituitary hormones". Science. 207 (4429): 373–378. Bibcode:1980Sci...207..373B. doi:10.1126/science.6153132. PMID   6153132.
  38. Sheldrick EL, Flint AP (July 1989). "Post-translational processing of oxytocin-neurophysin prohormone in the ovine corpus luteum: activity of peptidyl glycine alpha-amidating mono-oxygenase and concentrations of its cofactor, ascorbic acid". The Journal of Endocrinology. 122 (1): 313–322. doi:10.1677/joe.0.1220313. PMID   2769155.
  39. Luck MR, Jungclas B (September 1987). "Catecholamines and ascorbic acid as stimulators of bovine ovarian oxytocin secretion" (PDF). The Journal of Endocrinology. 114 (3): 423–430. doi:10.1677/joe.0.1140423. PMID   3668432. S2CID   24630906. Archived from the original (PDF) on 2019-02-22.
  40. Hornig D (September 1975). "Distribution of ascorbic acid, metabolites and analogues in man and animals". Annals of the New York Academy of Sciences. 258 (1): 103–118. Bibcode:1975NYASA.258..103H. doi:10.1111/j.1749-6632.1975.tb29271.x. PMID   1106295. S2CID   22881895.
  41. 1 2 Tsujimoto M, Hattori A (August 2005). "The oxytocinase subfamily of M1 aminopeptidases". Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics. 1751 (1): 9–18. doi:10.1016/j.bbapap.2004.09.011. PMID   16054015.
  42. Nomura S, Ito T, Yamamoto E, Sumigama S, Iwase A, Okada M, et al. (August 2005). "Gene regulation and physiological function of placental leucine aminopeptidase/oxytocinase during pregnancy". Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics. 1751 (1): 19–25. doi:10.1016/j.bbapap.2005.04.006. PMID   15894523.
  43. 1 2 Mizutani S, Yokosawa H, Tomoda Y (July 1992). "Degradation of oxytocin by the human placenta: effect of selective inhibitors" (PDF). Acta Endocrinologica. 127 (1): 76–80. doi:10.1530/acta.0.1270076. PMID   1355623. S2CID   21289122. Archived from the original (PDF) on 2019-02-24.
  44. Meisenberg G, Simmons WH (1984). "Amastatin potentiates the behavioral effects of vasopressin and oxytocin in mice". Peptides. 5 (3): 535–539. doi:10.1016/0196-9781(84)90083-4. PMID   6540873. S2CID   3881661.
  45. Stancampiano R, Melis MR, Argiolas A (1991). "Proteolytic conversion of oxytocin by brain synaptic membranes: role of aminopeptidases and endopeptidases". Peptides. 12 (5): 1119–1125. doi:10.1016/0196-9781(91)90068-z. PMID   1800950. S2CID   36706540.
  46. Itoh C, Watanabe M, Nagamatsu A, Soeda S, Kawarabayashi T, Shimeno H (January 1997). "Two molecular species of oxytocinase (L-cystine aminopeptidase) in human placenta: purification and characterization". Biological & Pharmaceutical Bulletin. 20 (1): 20–24. doi: 10.1248/bpb.20.20 . PMID   9013800.
  47. Sukhov RR, Walker LC, Rance NE, Price DL, Young WS (November 1993). "Vasopressin and oxytocin gene expression in the human hypothalamus". The Journal of Comparative Neurology. 337 (2): 295–306. doi:10.1002/cne.903370210. PMC   9883978 . PMID   8277003. S2CID   35174328.
  48. 1 2 3 Ross HE, Cole CD, Smith Y, Neumann ID, Landgraf R, Murphy AZ, et al. (September 2009). "Characterization of the oxytocin system regulating affiliative behavior in female prairie voles". Neuroscience. 162 (4): 892–903. doi:10.1016/j.neuroscience.2009.05.055. PMC   2744157 . PMID   19482070.
  49. Landgraf R, Neumann ID (2004). "Vasopressin and oxytocin release within the brain: a dynamic concept of multiple and variable modes of neuropeptide communication". Frontiers in Neuroendocrinology. 25 (3–4): 150–176. doi:10.1016/j.yfrne.2004.05.001. PMID   15589267. S2CID   30507377.
  50. Baribeau DA, Anagnostou E (2015). "Oxytocin and vasopressin: linking pituitary neuropeptides and their receptors to social neurocircuits". Frontiers in Neuroscience. 9: 335. doi: 10.3389/fnins.2015.00335 . PMC   4585313 . PMID   26441508.
  51. Wathes DC, Swann RW (May 1982). "Is oxytocin an ovarian hormone?". Nature. 297 (5863): 225–227. Bibcode:1982Natur.297..225W. doi:10.1038/297225a0. PMID   7078636. S2CID   4364778.
  52. Wathes DC, Swann RW, Pickering BT, Porter DG, Hull MG, Drife JO (August 1982). "Neurohypophysial hormones in the human ovary". Lancet. 2 (8295): 410–412. doi:10.1016/S0140-6736(82)90441-X. PMID   6124806. S2CID   42282964.
  53. Fields PA, Eldridge RK, Fuchs AR, Roberts RF, Fields MJ (April 1983). "Human placental and bovine corpora luteal oxytocin". Endocrinology. 112 (4): 1544–1546. doi:10.1210/endo-112-4-1544. PMID   6832059.
  54. Guldenaar SE, Pickering BT (1985). "Immunocytochemical evidence for the presence of oxytocin in rat testis". Cell and Tissue Research. 240 (2): 485–487. doi:10.1007/BF00222364. PMID   3995564. S2CID   34325145.
  55. Gauquelin G, Geelen G, Louis F, Allevard AM, Meunier C, Cuisinaud G, et al. (1983). "Presence of vasopressin, oxytocin and neurophysin in the retina of mammals, effect of light and darkness, comparison with the neuropeptide content of the neurohypophysis and the pineal gland". Peptides. 4 (4): 509–515. doi:10.1016/0196-9781(83)90056-6. PMID   6647119. S2CID   3848055.
  56. Ang VT, Jenkins JS (April 1984). "Neurohypophysial hormones in the adrenal medulla". The Journal of Clinical Endocrinology and Metabolism. 58 (4): 688–691. doi:10.1210/jcem-58-4-688. PMID   6699132.
  57. Geenen V, Legros JJ, Franchimont P, Baudrihaye M, Defresne MP, Boniver J (April 1986). "The neuroendocrine thymus: coexistence of oxytocin and neurophysin in the human thymus". Science. 232 (4749): 508–511. Bibcode:1986Sci...232..508G. doi:10.1126/science.3961493. hdl: 2268/16909 . PMID   3961493.
  58. Amico JA, Finn FM, Haldar J (November 1988). "Oxytocin and vasopressin are present in human and rat pancreas". The American Journal of the Medical Sciences. 296 (5): 303–307. doi:10.1097/00000441-198811000-00003. PMID   3195625. S2CID   20084873.
  59. Kukucka MA, Misra HP (1992). "HPLC determination of an oxytocin-like peptide produced by isolated guinea pig Leydig cells: stimulation by ascorbate". Archives of Andrology. 29 (2): 185–190. doi: 10.3109/01485019208987723 . PMID   1456839.
  60. [ dead link ]
  61. Venkatesh B, Si-Hoe SL, Murphy D, Brenner S (November 1997). "Transgenic rats reveal functional conservation of regulatory controls between the Fugu isotocin and rat oxytocin genes". Proceedings of the National Academy of Sciences of the United States of America. 94 (23): 12462–12466. Bibcode:1997PNAS...9412462V. doi: 10.1073/pnas.94.23.12462 . PMC   25001 . PMID   9356472.
  62. 1 2 3 4 Gimpl G, Fahrenholz F (April 2001). "The oxytocin receptor system: structure, function, and regulation" (PDF). Physiological Reviews. 81 (2): 629–683. doi:10.1152/physrev.2001.81.2.629. PMID   11274341. S2CID   13265083. Archived from the original (PDF) on 2020-11-16.
  63. Akinrinade I, Kareklas K, Teles MC, Reis TK, Gliksberg M, Petri G, et al. (March 2023). "Evolutionarily conserved role of oxytocin in social fear contagion in zebrafish". Science. 379 (6638): 1232–1237. Bibcode:2023Sci...379.1232A. doi:10.1126/science.abq5158. PMID   36952426.
  64. Quattropani A, Dorbais J, Covini D, Pittet PA, Colovray V, Thomas RJ, et al. (December 2005). "Discovery and development of a new class of potent, selective, orally active oxytocin receptor antagonists". Journal of Medicinal Chemistry. 48 (24): 7882–7905. doi:10.1021/jm050645f. PMID   16302826. S2CID   11213732.
  65. Holmes B (11 February 2022). "Oxytocin's effects aren't just about love". Knowable Magazine. doi: 10.1146/knowable-021122-1 . Retrieved 15 February 2022.
  66. Froemke RC, Young LJ (July 2021). "Oxytocin, Neural Plasticity, and Social Behavior". Annual Review of Neuroscience. 44 (1): 359–381. doi:10.1146/annurev-neuro-102320-102847. PMC   8604207 . PMID   33823654.
  67. Drakopoulos A, Moianos D, Prifti GM, Zoidis G, Decker M (July 2022). "Opioid Ligands Addressing Unconventional Binding Sites and More Than One Opioid Receptor Subtype". ChemMedChem. 17 (14): e202200169. doi:10.1002/cmdc.202200169. PMID   35560796.
  68. Kaczyńska K, Wojciechowski P (December 2021). "Non-Opioid Peptides Targeting Opioid Effects". Int J Mol Sci. 22 (24): 13619. doi: 10.3390/ijms222413619 . PMC   8709238 . PMID   34948415.
  69. Carter CS, Kingsbury MA (August 2022). "Oxytocin and oxygen: the evolution of a solution to the 'stress of life'". Philos Trans R Soc Lond B Biol Sci. 377 (1858): 20210054. doi:10.1098/rstb.2021.0054. PMC   9272143 . PMID   35856299.
  70. Meguro Y, Miyano K, Hirayama S, Yoshida Y, Ishibashi N, Ogino T, et al. (May 2018). "Neuropeptide oxytocin enhances μ opioid receptor signaling as a positive allosteric modulator". J Pharmacol Sci. 137 (1): 67–75. doi: 10.1016/j.jphs.2018.04.002 . PMID   29716811.
  71. Miyano K, Yoshida Y, Hirayama S, Takahashi H, Ono H, Meguro Y, et al. (October 2021). "Oxytocin Is a Positive Allosteric Modulator of κ-Opioid Receptors but Not δ-Opioid Receptors in the G Protein Signaling Pathway". Cells. 10 (10): 2651. doi: 10.3390/cells10102651 . PMC   8534029 . PMID   34685631.
  72. Mizuguchi T, Miyano K, Yamauchi R, Yoshida Y, Takahashi H, Yamazaki A, et al. (January 2023). "The first structure-activity relationship study of oxytocin as a positive allosteric modulator for the µ opioid receptor". Peptides. 159: 170901. doi:10.1016/j.peptides.2022.170901. PMID   36347314.
  73. Human Milk and Lactation at eMedicine
  74. MacGill M. "What is oxytocin, and what does it do?". Medical News Today. Heath Line Media. Retrieved March 29, 2017.
  75. 1 2 Takayanagi Y, Yoshida M, Bielsky IF, Ross HE, Kawamata M, Onaka T, et al. (November 2005). "Pervasive social deficits, but normal parturition, in oxytocin receptor-deficient mice". Proceedings of the National Academy of Sciences of the United States of America. 102 (44): 16096–16101. Bibcode:2005PNAS..10216096T. doi: 10.1073/pnas.0505312102 . PMC   1276060 . PMID   16249339.
  76. 1 2 Thackare H, Nicholson HD, Whittington K (2006-08-01). "Oxytocin--its role in male reproduction and new potential therapeutic uses". Human Reproduction Update. 12 (4): 437–448. doi: 10.1093/humupd/dmk002 . PMID   16436468.
  77. 1 2 3 Carmichael MS, Humbert R, Dixen J, Palmisano G, Greenleaf W, Davidson JM (January 1987). "Plasma oxytocin increases in the human sexual response". The Journal of Clinical Endocrinology and Metabolism. 64 (1): 27–31. doi:10.1210/jcem-64-1-27. PMID   3782434.
  78. Carmichael MS, Warburton VL, Dixen J, Davidson JM (February 1994). "Relationships among cardiovascular, muscular, and oxytocin responses during human sexual activity". Archives of Sexual Behavior. 23 (1): 59–79. doi:10.1007/BF01541618. PMID   8135652. S2CID   36539568.
  79. Blaicher W, Gruber D, Bieglmayer C, Blaicher AM, Knogler W, Huber JC (1999). "The role of oxytocin in relation to female sexual arousal". Gynecologic and Obstetric Investigation. 47 (2): 125–126. doi:10.1159/000010075. PMID   9949283. S2CID   43036197.
  80. Anderson-Hunt M, Dennerstein L (1995). "Oxytocin and female sexuality". Gynecologic and Obstetric Investigation. 40 (4): 217–221. doi:10.1159/000292340. PMID   8586300.
  81. Murphy MR, Seckl JR, Burton S, Checkley SA, Lightman SL (October 1987). "Changes in oxytocin and vasopressin secretion during sexual activity in men". The Journal of Clinical Endocrinology and Metabolism. 65 (4): 738–741. doi: 10.1210/jcem-65-4-738 . PMID   3654918.
  82. Krüger TH, Haake P, Chereath D, Knapp W, Janssen OE, Exton MS, et al. (April 2003). "Specificity of the neuroendocrine response to orgasm during sexual arousal in men". The Journal of Endocrinology. 177 (1): 57–64. doi: 10.1677/joe.0.1770057 . PMID   12697037.
  83. Paquin J, Danalache BA, Jankowski M, McCann SM, Gutkowska J (July 2002). "Oxytocin induces differentiation of P19 embryonic stem cells to cardiomyocytes". Proceedings of the National Academy of Sciences of the United States of America. 99 (14): 9550–9555. Bibcode:2002PNAS...99.9550P. doi: 10.1073/pnas.152302499 . PMC   123178 . PMID   12093924.
  84. Jankowski M, Danalache B, Wang D, Bhat P, Hajjar F, Marcinkiewicz M, et al. (August 2004). "Oxytocin in cardiac ontogeny". Proceedings of the National Academy of Sciences of the United States of America. 101 (35): 13074–13079. Bibcode:2004PNAS..10113074J. doi: 10.1073/pnas.0405324101 . PMC   516519 . PMID   15316117.
  85. Hartwig W (1989). Endokrynologia praktyczna. Warsaw: Państwowy Zakład Wydawnictw Lekarskich. ISBN   978-83-200-1415-0.[ page needed ]
  86. Tyzio R, Cossart R, Khalilov I, Minlebaev M, Hübner CA, Represa A, et al. (December 2006). "Maternal oxytocin triggers a transient inhibitory switch in GABA signaling in the fetal brain during delivery" (PDF). Science. 314 (5806): 1788–1792. Bibcode:2006Sci...314.1788T. doi:10.1126/science.1133212. PMID   17170309. S2CID   85151049.
  87. Atasoy D, Betley JN, Su HH, Sternson SM (August 2012). "Deconstruction of a neural circuit for hunger". Nature. 488 (7410): 172–177. Bibcode:2012Natur.488..172A. doi:10.1038/nature11270. PMC   3416931 . PMID   22801496.
  88. Odekunle EA, Semmens DC, Martynyuk N, Tinoco AB, Garewal AK, Patel RR, et al. (July 2019). "Ancient role of vasopressin/oxytocin-type neuropeptides as regulators of feeding revealed in an echinoderm". BMC Biology. 17 (1): 60. doi: 10.1186/s12915-019-0680-2 . PMC   6668147 . PMID   31362737.
  89. 1 2 Jacob S, Brune CW, Carter CS, Leventhal BL, Lord C, Cook EH (April 2007). "Association of the oxytocin receptor gene (OXTR) in Caucasian children and adolescents with autism". Neuroscience Letters. 417 (1): 6–9. doi:10.1016/j.neulet.2007.02.001. PMC   2705963 . PMID   17383819.
  90. Wermter AK, Kamp-Becker I, Hesse P, Schulte-Körne G, Strauch K, Remschmidt H (March 2010). "Evidence for the involvement of genetic variation in the oxytocin receptor gene (OXTR) in the etiology of autistic disorders on high-functioning level". American Journal of Medical Genetics. Part B, Neuropsychiatric Genetics. 153B (2): 629–639. doi:10.1002/ajmg.b.31032. PMID   19777562. S2CID   15970613.
  91. Leng G, Ludwig M (February 2016). "Intranasal Oxytocin: Myths and Delusions". Biological Psychiatry. 79 (3): 243–250. doi:10.1016/j.biopsych.2015.05.003. PMID   26049207.
  92. Audunsdottir K, Sartorius AM, Kang H, Glaser BD, Boen R, Nærland T, et al. (September 2024). "The effects of oxytocin administration on social and routinized behaviors in autism: A preregistered systematic review and meta-analysis". Psychoneuroendocrinology. 167: 107067. doi:10.1016/j.psyneuen.2024.107067. PMID   38815399.
  93. Phan JM, Dwyer P, Elsherif MM, Friedel E, Kapp SK (October 2024). "Oxytocin in autism: Rethinking treatment and research through a neurodivergent perspective". Psychoneuroendocrinology. 171: 107220. doi:10.1016/j.psyneuen.2024.107220. PMID   39471539.
  94. Fletcher-Watson S, Brook K, Hallett S, Murray F, Crompton CJ (June 2021). "Inclusive Practices for Neurodevelopmental Research". Current Developmental Disorders Reports. 8 (2): 88–97. doi:10.1007/s40474-021-00227-z. ISSN   2196-2987.
  95. Wilson E, Ramage FJ, Wever KE, Sena ES, Macleod MR, Currie GL (July 2023). "Designing, conducting, and reporting reproducible animal experiments". The Journal of Endocrinology. 258 (1). doi:10.1530/JOE-22-0330. PMC   10304908 . PMID   37074416.
  96. Dayi A, Cetin F, Sisman AR, Aksu I, Tas A, Gönenc S, et al. (January 2015). "The effects of oxytocin on cognitive defect caused by chronic restraint stress applied to adolescent rats and on hippocampal VEGF and BDNF levels". Medical Science Monitor. 21: 69–75. doi:10.12659/MSM.893159. PMC   4294596 . PMID   25559382.
  97. Leuner B, Caponiti JM, Gould E (April 2012). "Oxytocin stimulates adult neurogenesis even under conditions of stress and elevated glucocorticoids". Hippocampus. 22 (4): 861–868. doi:10.1002/hipo.20947. PMC   4756590 . PMID   21692136.
  98. Ye C, Cheng M, Ma L, Zhang T, Sun Z, Yu C, et al. (May 2022). "Oxytocin Nanogels Inhibit Innate Inflammatory Response for Early Intervention in Alzheimer's Disease". ACS Applied Materials & Interfaces. 14 (19): 21822–21835. doi:10.1021/acsami.2c00007. PMID   35510352. S2CID   248526969.
  99. Vacek M (2002). "High on Fidelity: What can voles teach us about monogamy?". American Scientist. Archived from the original on October 15, 2006.
  100. Odendaal JS, Meintjes RA (May 2003). "Neurophysiological correlates of affiliative behaviour between humans and dogs". Veterinary Journal. 165 (3): 296–301. doi:10.1016/S1090-0233(02)00237-X. PMID   12672376.
  101. van Leengoed E, Kerker E, Swanson HH (February 1987). "Inhibition of post-partum maternal behaviour in the rat by injecting an oxytocin antagonist into the cerebral ventricles". The Journal of Endocrinology. 112 (2): 275–282. doi:10.1677/joe.0.1120275. PMID   3819639.
  102. Kendrick KM (December 2004). "The neurobiology of social bonds". Journal of Neuroendocrinology. 16 (12). British Society for Neuroendocrinology: 1007–1008. doi:10.1111/j.1365-2826.2004.01262.x. PMID   15667456. S2CID   21635457. Archived from the original on 2009-04-29. Retrieved 2009-04-13.
  103. Bick J, Dozier M (January 2010). "Mothers' and Children's Concentrations of Oxytocin Following Close, Physical Interactions with Biological and Non-biological Children". Developmental Psychobiology. 52 (1): 100–107. doi:10.1002/dev.20411. PMC   2953948 . PMID   20953313.
  104. Shalvi S, De Dreu CK (April 2014). "Oxytocin promotes group-serving dishonesty". Proceedings of the National Academy of Sciences of the United States of America. 111 (15): 5503–5507. Bibcode:2014PNAS..111.5503S. doi: 10.1073/pnas.1400724111 . PMC   3992689 . PMID   24706799.
  105. Science Direct: Decreased oxytocin plasma levels and oxytocin receptor expression associated with aggressive behavior in aggressive-impulsive disorders
  106. De Dreu CK, Shalvi S, Greer LL, Van Kleef GA, Handgraaf MJ (2012). "Oxytocin motivates non-cooperation in intergroup conflict to protect vulnerable in-group members". PLOS ONE. 7 (11): e46751. Bibcode:2012PLoSO...746751D. doi: 10.1371/journal.pone.0046751 . PMC   3492361 . PMID   23144787.
  107. Stallen M, De Dreu CK, Shalvi S, Smidts A, Sanfey AG (2012). "The herding hormone: oxytocin stimulates in-group conformity". Psychological Science. 23 (11): 1288–1292. doi:10.1177/0956797612446026. hdl: 2066/121872 . PMID   22991128. S2CID   16255677.
  108. 1 2 3 De Dreu CK, Greer LL, Van Kleef GA, Shalvi S, Handgraaf MJ (January 2011). "Oxytocin promotes human ethnocentrism". Proceedings of the National Academy of Sciences of the United States of America. 108 (4): 1262–1266. Bibcode:2011PNAS..108.1262D. doi: 10.1073/pnas.1015316108 . PMC   3029708 . PMID   21220339.
  109. Ma X, Luo L, Geng Y, Zhao W, Zhang Q, Kendrick KM (2014). "Oxytocin increases liking for a country's people and national flag but not for other cultural symbols or consumer products". Frontiers in Behavioral Neuroscience. 8: 266. doi: 10.3389/fnbeh.2014.00266 . PMC   4122242 . PMID   25140135.
  110. Kovács GL, Sarnyai Z, Szabó G (November 1998). "Oxytocin and addiction: a review". Psychoneuroendocrinology. 23 (8): 945–962. doi:10.1016/S0306-4530(98)00064-X. PMID   9924746. S2CID   31674417.
  111. Thompson MR, Callaghan PD, Hunt GE, Cornish JL, McGregor IS (May 2007). "A role for oxytocin and 5-HT(1A) receptors in the prosocial effects of 3,4 methylenedioxymethamphetamine ("ecstasy")". Neuroscience. 146 (2): 509–514. doi:10.1016/j.neuroscience.2007.02.032. PMID   17383105. S2CID   15617471.
  112. Uvnäs-Moberg K, Hillegaart V, Alster P, Ahlenius S (1996). "Effects of 5-HT agonists, selective for different receptor subtypes, on oxytocin, CCK, gastrin and somatostatin plasma levels in the rat". Neuropharmacology. 35 (11): 1635–1640. doi:10.1016/S0028-3908(96)00078-0. PMID   9025112. S2CID   44375951.
  113. Chiodera P, Volpi R, Capretti L, Caffarri G, Magotti MG, Coiro V (April 1996). "Different effects of the serotonergic agonists buspirone and sumatriptan on the posterior pituitary hormonal responses to hypoglycemia in humans". Neuropeptides. 30 (2): 187–192. doi:10.1016/S0143-4179(96)90086-4. PMID   8771561. S2CID   13734738.
  114. Buisman-Pijlman FT, Sumracki NM, Gordon JJ, Hull PR, Carter CS, Tops M (April 2014). "Individual differences underlying susceptibility to addiction: Role for the endogenous oxytocin system". Pharmacology, Biochemistry, and Behavior. 119: 22–38. doi: 10.1016/j.pbb.2013.09.005 . PMID   24056025.
  115. Grillon C, Krimsky M, Charney DR, Vytal K, Ernst M, Cornwell B (September 2013). "Oxytocin increases anxiety to unpredictable threat". Molecular Psychiatry. 18 (9): 958–960. doi:10.1038/mp.2012.156. PMC   3930442 . PMID   23147382.
  116. 1 2 Guzmán YF, Tronson NC, Jovasevic V, Sato K, Guedea AL, Mizukami H, et al. (September 2013). "Fear-enhancing effects of septal oxytocin receptors". Nature Neuroscience. 16 (9): 1185–1187. doi:10.1038/nn.3465. PMC   3758455 . PMID   23872596.
  117. 1 2 3 Theodoridou A, Penton-Voak IS, Rowe AC (2013). "A direct examination of the effect of intranasal administration of oxytocin on approach-avoidance motor responses to emotional stimuli". PLOS ONE. 8 (2): e58113. Bibcode:2013PLoSO...858113T. doi: 10.1371/journal.pone.0058113 . PMC   3585234 . PMID   23469148.
  118. Ibukun Akinrinade, Kyriacos Kareklas, Magda C. Teles, Thais K. Reis, Michael Gliksberg, Giovanni Petri, Gil Levkowitz, Rui F. Oliveira, Evolutionarily conserved role of oxytocin in social fear contagion in zebrafish , Science (magazine), March 23, 2023
  119. Larson, Christina, A fish can sense another's fear, a study shows , Associated Press, March 23, 2023
  120. Kirsch P, Esslinger C, Chen Q, Mier D, Lis S, Siddhanti S, et al. (December 2005). "Oxytocin modulates neural circuitry for social cognition and fear in humans". The Journal of Neuroscience. 25 (49): 11489–11493. doi:10.1523/JNEUROSCI.3984-05.2005. PMC   6725903 . PMID   16339042.
  121. Huber D, Veinante P, Stoop R (April 2005). "Vasopressin and oxytocin excite distinct neuronal populations in the central amygdala". Science. 308 (5719): 245–248. Bibcode:2005Sci...308..245H. doi:10.1126/SCIENCE.1105636. PMID   15821089. S2CID   40887741.
  122. Viviani D, Charlet A, van den Burg E, Robinet C, Hurni N, Abatis M, et al. (July 2011). "Oxytocin selectively gates fear responses through distinct outputs from the central amygdala". Science. 333 (6038): 104–107. Bibcode:2011Sci...333..104V. doi:10.1126/SCIENCE.1201043. PMID   21719680. S2CID   20446890.
  123. Shamay-Tsoory SG, Fischer M, Dvash J, Harari H, Perach-Bloom N, Levkovitz Y (November 2009). "Intranasal administration of oxytocin increases envy and schadenfreude (gloating)". Biological Psychiatry. 66 (9): 864–870. doi:10.1016/j.biopsych.2009.06.009. PMID   19640508. S2CID   20396036.
  124. Fischer-Shofty M, Shamay-Tsoory SG, Harari H, Levkovitz Y (January 2010). "The effect of intranasal administration of oxytocin on fear recognition". Neuropsychologia. 48 (1): 179–184. doi:10.1016/j.neuropsychologia.2009.09.003. PMID   19747930. S2CID   34778485.
  125. 1 2 Matsuzaki M, Matsushita H, Tomizawa K, Matsui H (November 2012). "Oxytocin: a therapeutic target for mental disorders". The Journal of Physiological Sciences. 62 (6): 441–444. doi: 10.1007/s12576-012-0232-9 . PMC   10717158 . PMID   23007624. S2CID   17860416.
  126. McQuaid RJ, McInnis OA, Abizaid A, Anisman H (September 2014). "Making room for oxytocin in understanding depression". Neuroscience and Biobehavioral Reviews. 45: 305–322. doi:10.1016/j.neubiorev.2014.07.005. PMID   25025656. S2CID   32062939.
  127. 1 2 Shalev I, Ebstein RP (2015). Social Hormones and Human Behavior: What Do We Know and Where Do We Go from Here. Frontiers Media SA. pp. 51–. ISBN   978-2-88919-407-0.
  128. Hicks C, Ramos L, Reekie T, Misagh GH, Narlawar R, Kassiou M, et al. (June 2014). "Body temperature and cardiac changes induced by peripherally administered oxytocin, vasopressin and the non-peptide oxytocin receptor agonist WAY 267,464: a biotelemetry study in rats". British Journal of Pharmacology. 171 (11): 2868–2887. doi:10.1111/bph.12613. PMC   4243861 . PMID   24641248.
  129. Manning M, Misicka A, Olma A, Bankowski K, Stoev S, Chini B, et al. (April 2012). "Oxytocin and vasopressin agonists and antagonists as research tools and potential therapeutics". Journal of Neuroendocrinology. 24 (4): 609–628. doi:10.1111/j.1365-2826.2012.02303.x. PMC   3490377 . PMID   22375852.
  130. Matsushita H, Tomizawa K, Okimoto N, Nishiki T, Ohmori I, Matsui H (October 2010). "Oxytocin mediates the antidepressant effects of mating behavior in male mice". Neuroscience Research. 68 (2): 151–153. doi:10.1016/j.neures.2010.06.007. PMID   20600375. S2CID   207152048.
  131. Phan J, Alhassen L, Argelagos A, Alhassen W, Vachirakorntong B, Lin Z, et al. (August 2020). "Mating and parenting experiences sculpture mood-modulating effects of oxytocin-MCH signaling". Scientific Reports. 10 (1): 13611. Bibcode:2020NatSR..1013611P. doi:10.1038/s41598-020-70667-x. PMC   7423941 . PMID   32788646.
  132. Zhang Z, Klyachko V, Jackson MB (October 2007). "Blockade of phosphodiesterase Type 5 enhances rat neurohypophysial excitability and electrically evoked oxytocin release". The Journal of Physiology. 584 (Pt 1): 137–147. doi:10.1113/jphysiol.2007.139303. PMC   2277045 . PMID   17690141.
  133. Matsushita H, Matsuzaki M, Han XJ, Nishiki TI, Ohmori I, Michiue H, et al. (January 2012). "Antidepressant-like effect of sildenafil through oxytocin-dependent cyclic AMP response element-binding protein phosphorylation". Neuroscience. 200: 13–18. doi:10.1016/j.neuroscience.2011.11.001. PMID   22088430. S2CID   12502639.
  134. 1 2 Lischke A, Gamer M, Berger C, Grossmann A, Hauenstein K, Heinrichs M, et al. (September 2012). "Oxytocin increases amygdala reactivity to threatening scenes in females". Psychoneuroendocrinology. 37 (9): 1431–1438. doi:10.1016/j.psyneuen.2012.01.011. PMID   22365820. S2CID   7981815.
  135. Okabe S, Kitano K, Nagasawa M, Mogi K, Kikusui T (June 2013). "Testosterone inhibits facilitating effects of parenting experience on parental behavior and the oxytocin neural system in mice". Physiology & Behavior. 118: 159–164. doi:10.1016/j.physbeh.2013.05.017. PMID   23685236. S2CID   46790892.
  136. 1 2 Hurlemann R, Patin A, Onur OA, Cohen MX, Baumgartner T, Metzler S, et al. (April 2010). "Oxytocin enhances amygdala-dependent, socially reinforced learning and emotional empathy in humans". The Journal of Neuroscience. 30 (14): 4999–5007. doi:10.1523/JNEUROSCI.5538-09.2010. PMC   6632777 . PMID   20371820.
  137. "Oxytocin: The love hormone". Harvard Health. 2021-07-20. Retrieved 2023-11-01.
  138. Zak PJ, Stanton AA, Ahmadi S (November 2007). Brosnan S (ed.). "Oxytocin increases generosity in humans". PLOS ONE. 2 (11): e1128. Bibcode:2007PLoSO...2.1128Z. doi: 10.1371/journal.pone.0001128 . PMC   2040517 . PMID   17987115.
  139. Conlisk J (2011). "Professor Zak's empirical studies on trust and oxytocin". J Econ Behav Organizat. 78 (1–2): 160–66. doi:10.1016/j.jebo.2011.01.002.
  140. Domes G, Heinrichs M, Michel A, Berger C, Herpertz SC (March 2007). "Oxytocin improves "mind-reading" in humans". Biological Psychiatry. 61 (6): 731–733. doi:10.1016/j.biopsych.2006.07.015. PMID   17137561. S2CID   3125539.
  141. Guastella AJ, Mitchell PB, Dadds MR (January 2008). "Oxytocin increases gaze to the eye region of human faces". Biological Psychiatry. 63 (1): 3–5. doi:10.1016/j.biopsych.2007.06.026. PMID   17888410. S2CID   11974058.
  142. Singer T, Snozzi R, Bird G, Petrovic P, Silani G, Heinrichs M, et al. (December 2008). "Effects of oxytocin and prosocial behavior on brain responses to direct and vicariously experienced pain". Emotion. 8 (6): 781–791. doi:10.1037/a0014195. PMC   2672051 . PMID   19102589.
  143. Wittig RM, Crockford C, Deschner T, Langergraber KE, Ziegler TE, Zuberbühler K (March 2014). "Food sharing is linked to urinary oxytocin levels and bonding in related and unrelated wild chimpanzees". Proceedings. Biological Sciences. 281 (1778): 20133096. doi:10.1098/rspb.2013.3096. PMC   3906952 . PMID   24430853.
  144. 1 2 Kosfeld M, Heinrichs M, Zak PJ, Fischbacher U, Fehr E (June 2005). "Oxytocin increases trust in humans". Nature. 435 (7042): 673–676. Bibcode:2005Natur.435..673K. doi:10.1038/nature03701. PMID   15931222. S2CID   1234727.
  145. 1 2 Theodoridou A, Rowe AC, Penton-Voak IS, Rogers PJ (June 2009). "Oxytocin and social perception: oxytocin increases perceived facial trustworthiness and attractiveness". Hormones and Behavior. 56 (1): 128–132. doi:10.1016/j.yhbeh.2009.03.019. PMID   19344725. S2CID   12639878.
  146. 1 2 Lane A, Luminet O, Rimé B, Gross JJ, de Timary P, Mikolajczak M (2013). "Oxytocin increases willingness to socially share one's emotions". International Journal of Psychology. 48 (4): 676–681. doi:10.1080/00207594.2012.677540. PMID   22554106.
  147. 1 2 Cardoso C, Ellenbogen MA, Serravalle L, Linnen AM (November 2013). "Stress-induced negative mood moderates the relation between oxytocin administration and trust: evidence for the tend-and-befriend response to stress?". Psychoneuroendocrinology. 38 (11): 2800–2804. doi:10.1016/j.psyneuen.2013.05.006. PMID   23768973. S2CID   25090544.
  148. Carey B (2005-06-02). "Hormone Dose May Increase People's Trust in Strangers". The New York Times. ISSN   0362-4331 . Retrieved 2022-07-22.
  149. Baumgartner T, Heinrichs M, Vonlanthen A, Fischbacher U, Fehr E (May 2008). "Oxytocin shapes the neural circuitry of trust and trust adaptation in humans". Neuron. 58 (4): 639–650. doi: 10.1016/j.neuron.2008.04.009 . PMID   18498743. S2CID   1432797.
  150. Kosfeld M, Heinrichs M, Zak PJ, Fischbacher U, Fehr E (June 2005). "Oxytocin increases trust in humans". Nature. 435 (7042): 673–676. Bibcode:2005Natur.435..673K. doi:10.1038/nature03701. PMID   15931222. S2CID   1234727.
  151. Tabak BA, McCullough ME, Carver CS, Pedersen EJ, Cuccaro ML (June 2014). "Variation in oxytocin receptor gene (OXTR) polymorphisms is associated with emotional and behavioral reactions to betrayal". Social Cognitive and Affective Neuroscience. 9 (6): 810–816. doi:10.1093/scan/nst042. PMC   4040089 . PMID   23547247.
  152. 1 2 Marazziti D, Dell'Osso B, Baroni S, Mungai F, Catena M, Rucci P, et al. (October 2006). "A relationship between oxytocin and anxiety of romantic attachment". Clinical Practice and Epidemiology in Mental Health. 2 (1): 28. doi: 10.1186/1745-0179-2-28 . PMC   1621060 . PMID   17034623.
  153. Shalvi S, De Dreu CK (April 2014). "Oxytocin promotes group-serving dishonesty". Proceedings of the National Academy of Sciences of the United States of America. 111 (15): 5503–5507. Bibcode:2014PNAS..111.5503S. doi: 10.1073/pnas.1400724111 . PMC   3992689 . PMID   24706799.
  154. Scheele D, Striepens N, Güntürkün O, Deutschländer S, Maier W, Kendrick KM, et al. (November 2012). "Oxytocin modulates social distance between males and females". The Journal of Neuroscience. 32 (46): 16074–16079. doi:10.1523/JNEUROSCI.2755-12.2012. PMC   6794013 . PMID   23152592.
  155. Malik AI, Zai CC, Abu Z, Nowrouzi B, Beitchman JH (July 2012). "The role of oxytocin and oxytocin receptor gene variants in childhood-onset aggression". Genes, Brain and Behavior. 11 (5): 545–551. doi: 10.1111/j.1601-183X.2012.00776.x . PMID   22372486. S2CID   38807759.
  156. Zak PJ, Kurzban R, Matzner WT (December 2004). "The neurobiology of trust". Annals of the New York Academy of Sciences. 1032 (1): 224–227. Bibcode:2004NYASA1032..224Z. doi:10.1196/annals.1314.025. PMID   15677415. S2CID   45599465.
  157. Buemann B, Marazziti D, Uvnäs-Moberg K (June 2021). "Can intravenous oxytocin infusion counteract hyperinflammation in COVID-19 infected patients?". The World Journal of Biological Psychiatry. 22 (5): 387–398. doi: 10.1080/15622975.2020.1814408 . PMID   32914674. S2CID   221623635.
  158. Gouin JP, Carter CS, Pournajafi-Nazarloo H, Glaser R, Malarkey WB, Loving TJ, et al. (August 2010). "Marital behavior, oxytocin, vasopressin, and wound healing". Psychoneuroendocrinology. 35 (7): 1082–1090. doi:10.1016/j.psyneuen.2010.01.009. PMC   2888874 . PMID   20144509.
  159. Nakajima M, Görlich A, Heintz N (October 2014). "Oxytocin modulates female sociosexual behavior through a specific class of prefrontal cortical interneurons". Cell. 159 (2): 295–305. doi:10.1016/j.cell.2014.09.020. PMC   4206218 . PMID   25303526.
  160. Heinrichs M, Baumgartner T, Kirschbaum C, Ehlert U (December 2003). "Social support and oxytocin interact to suppress cortisol and subjective responses to psychosocial stress". Biological Psychiatry. 54 (12): 1389–1398. doi:10.1016/S0006-3223(03)00465-7. PMID   14675803. S2CID   20632786.
  161. Matsushita H, Latt HM, Koga Y, Nishiki T, Matsui H (October 2019). "Oxytocin and Stress: Neural Mechanisms, Stress-Related Disorders, and Therapeutic Approaches". Neuroscience. 417: 1–10. doi:10.1016/j.neuroscience.2019.07.046. PMID   31400490. S2CID   199527439.
  162. Wei D, Lee D, Cox CD, Karsten CA, Peñagarikano O, Geschwind DH, et al. (November 2015). "Endocannabinoid signaling mediates oxytocin-driven social reward". Proceedings of the National Academy of Sciences of the United States of America. 112 (45): 14084–14089. Bibcode:2015PNAS..11214084W. doi: 10.1073/pnas.1509795112 . PMC   4653148 . PMID   26504214.
  163. Lerer E, Levi S, Salomon S, Darvasi A, Yirmiya N, Ebstein RP (October 2008). "Association between the oxytocin receptor (OXTR) gene and autism: relationship to Vineland Adaptive Behavior Scales and cognition". Molecular Psychiatry. 13 (10): 980–988. doi: 10.1038/sj.mp.4002087 . PMID   17893705. S2CID   19513481.
  164. Chang WH, Lee IH, Chen KC, Chi MH, Chiu NT, Yao WJ, et al. (September 2014). "Oxytocin receptor gene rs53576 polymorphism modulates oxytocin-dopamine interaction and neuroticism traits--a SPECT study". Psychoneuroendocrinology. 47: 212–220. doi:10.1016/j.psyneuen.2014.05.020. PMID   25001970. S2CID   22163043.
  165. 1 2 Burtis CA, Ashwood ER, Bruns DE (2012). Tietz Textbook of Clinical Chemistry and Molecular Diagnostics (5th ed.). Elsevier Health Sciences. p. 1833. ISBN   978-1-4557-5942-2.
  166. "WHO International Standard OXYTOCIN 4th International Standard NIBSC code: 76/575: Instructions for use (Version 4.0, Dated 30/04/2013)" (PDF). Nibsc.org. Retrieved 5 March 2022.
  167. Lee AG, Cool DR, Grunwald WC, Neal DE, Buckmaster CL, Cheng MY, et al. (August 2011). "A novel form of oxytocin in New World monkeys". Biology Letters. 7 (4): 584–587. doi:10.1098/rsbl.2011.0107. PMC   3130245 . PMID   21411453.
  168. Vargas-Pinilla P, Paixão-Côrtes VR, Paré P, Tovo-Rodrigues L, Vieira CM, Xavier A, et al. (January 2015). "Evolutionary pattern in the OXT-OXTR system in primates: coevolution and positive selection footprints". Proceedings of the National Academy of Sciences of the United States of America. 112 (1): 88–93. Bibcode:2015PNAS..112...88V. doi: 10.1073/pnas.1419399112 . PMC   4291646 . PMID   25535371.
  169. Ren D, Lu G, Moriyama H, Mustoe AC, Harrison EB, French JA (2015). "Genetic diversity in oxytocin ligands and receptors in New World monkeys". PLOS ONE. 10 (5): e0125775. Bibcode:2015PLoSO..1025775R. doi: 10.1371/journal.pone.0125775 . PMC   4418824 . PMID   25938568.
  170. Moriyama E, Kataoka H (2015-06-30). "Automated Analysis of Oxytocin by On-Line in-Tube Solid-Phase Microextraction Coupled with Liquid Chromatography-Tandem Mass Spectrometry". Chromatography. 2 (3): 382–391. doi: 10.3390/chromatography2030382 . ISSN   2227-9075.
  171. Wang L, Marti DW, Anderson RE (August 2019). "Development and Validation of a Simple LC-MS Method for the Quantification of Oxytocin in Dog Saliva". Molecules. 24 (17): 3079. doi: 10.3390/molecules24173079 . PMC   6749683 . PMID   31450590.
  172. Franke AA, Li X, Menden A, Lee MR, Lai JF (January 2019). "Oxytocin analysis from human serum, urine, and saliva by orbitrap liquid chromatography-mass spectrometry". Drug Testing and Analysis. 11 (1): 119–128. doi:10.1002/dta.2475. PMC   6349498 . PMID   30091853.
  173. Du Vigneaud V, Ressler C, Swan JM, Roberts CW, Katsoyannis PG (1954). "The Synthesis of Oxytocin". Journal of the American Chemical Society . 76 (12): 3115–21. doi:10.1021/ja01641a004.
  174. "The Nobel Prize in Chemistry 1955". Nobelprize.org. Nobel Media AB . Retrieved 17 November 2016.
  175. Leng G, Brown CH, Russell JA (April 1999). "Physiological pathways regulating the activity of magnocellular neurosecretory cells". Progress in Neurobiology. 57 (6): 625–655. doi:10.1016/s0301-0082(98)00072-0. PMID   10221785. S2CID   240663.
  176. Nashar PE, Whitfield AA, Mikusek J, Reekie TA (2022). "The Current Status of Drug Discovery for the Oxytocin Receptor". Oxytocin. Methods Mol Biol. Vol. 2384. New York, NY: Springer. pp. 153–174. doi:10.1007/978-1-0716-1759-5_10. ISBN   978-1-0716-1758-8. PMID   34550574. S2CID   239090096.
  177. Gulliver D, Werry E, Reekie TA, Katte TA, Jorgensen W, Kassiou M (January 2019). "Targeting the Oxytocin System: New Pharmacotherapeutic Approaches". Trends Pharmacol Sci. 40 (1): 22–37. doi:10.1016/j.tips.2018.11.001. hdl: 1959.4/unsworks_81554 . PMID   30509888. S2CID   54559394.
  178. Frantz MC, Pellissier LP, Pflimlin E, Loison S, Gandía J, Marsol C, et al. (October 2018). "LIT-001, the First Nonpeptide Oxytocin Receptor Agonist that Improves Social Interaction in a Mouse Model of Autism" (PDF). J Med Chem. 61 (19): 8670–8692. doi:10.1021/acs.jmedchem.8b00697. PMID   30199637. S2CID   52181935.

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