Clinical data | |
---|---|
Pronunciation | /ˌveɪzoʊˈprɛsɪn/ |
Other names | Antidiuretic hormone (ADH); arginine vasopressin (AVP); argipressin |
ATC code | |
Physiological data | |
Source tissues | Supraoptic nucleus; paraventricular nucleus of hypothalamus |
Target tissues | System-wide |
Receptors | V1A, V1B, V2, OXTR |
Agonists | Felypressin, desmopressin |
Antagonists | Diuretics |
Metabolism | Predominantly in the liver and kidneys |
Pharmacokinetic data | |
Protein binding | 1% |
Metabolism | Predominantly in the liver and kidneys |
Elimination half-life | 10–20 minutes |
Excretion | Urine |
Identifiers | |
| |
CAS Number | |
PubChem CID | |
IUPHAR/BPS | |
DrugBank | |
ChemSpider | |
UNII | |
KEGG | |
ChEBI | |
ChEMBL | |
CompTox Dashboard (EPA) | |
Chemical and physical data | |
Formula | C46H65N15O12S2 |
Molar mass | 1084.24 g·mol−1 |
3D model (JSmol) | |
Density | 1.6±0.1 g/cm3 |
| |
|
Human vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP) or argipressin, [5] is a hormone synthesized from the AVP gene as a peptide prohormone in neurons in the hypothalamus, [6] 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. [7] [8] [9]
A third function is possible. Some AVP may be released directly into the brain from the hypothalamus, and may play an important role in social behavior, sexual motivation and pair bonding, and maternal responses to stress. [10]
Vasopressin induces differentiation of stem cells into cardiomyocytes and promotes heart muscle homeostasis. [11]
It has a very short half-life, between 16 and 24 minutes. [9]
Vasopressin regulates the tonicity of body fluids. It is released from the posterior pituitary in response to hypertonicity and causes the kidneys to reabsorb solute-free water and return it to the circulation from the tubules of the nephron, thus returning the tonicity of the body fluids toward normal. An incidental consequence of this renal reabsorption of water is concentrated urine and reduced urine volume. AVP released in high concentrations may also raise blood pressure by inducing moderate vasoconstriction. [12]
AVP also may have a variety of neurological effects on the brain. It may influence pair-bonding in voles. The high-density distributions of vasopressin receptor AVPr1a in prairie vole ventral forebrain regions have been shown to facilitate and coordinate reward circuits during partner preference formation, critical for pair bond formation. [13]
A very similar substance, lysine vasopressin (LVP) or lypressin, has the same function in pigs and its synthetic version was used in human AVP deficiency, although it has been largely replaced by desmopressin. [14]
Vasopressin has three main effects which are:
The hormone vasopressin also stimulates the activity of NKCC2. Vasopressin stimulates sodium chloride reabsorption in the thick ascending limb of the nephron by activating signaling pathways. Vasopressin increases the traffic of NKCC2 to the membrane and phosphorylates some serine and threonine sites on the cytoplasmic N-terminal of the NKCC2 located in the membrane, increasing its activity. Increased NKCC2 activity aids in water reabsorption in the collecting duct through aquaporin 2 channels by creating a hypo-osmotic filtrate. [19] [20]
Vasopressin released within the brain may have several actions:
Vasopressin is regulated by AVP gene expression which is managed by major clock controlled genes. In this circadian circuit known as the transcription-translation feedback loop (TTFL), Per2 protein accumulates and is phosphorylated by CK1E. Per2 subsequently inhibits the transcription factors Clock and BMAL1 in order to reduce Per2 protein levels in the cell. [24] At the same time, Per2 also inhibits the transcription factors for the AVP gene in order to regulate its expression, the expression of vasopressin, and other AVP gene products. [25]
Many factors influence the secretion of vasopressin:
The physiological stimulus for secretion of vasopressin is increased osmolality of the plasma, monitored by the hypothalamus. A decreased arterial blood volume, (such as can occur in cirrhosis, nephrosis, and heart failure), stimulates secretion, even in the face of decreased osmolality of the plasma: it supersedes osmolality, but with a milder effect. In other words, the unloading of baroreceptors when the arterial blood volume is low stimulates vasopressin secretion despite the presence of hypoosmolality (hyponatremia). [29]
The AVP that is measured in peripheral blood is almost all derived from secretion from the posterior pituitary gland (except in cases of AVP-secreting tumours). Vasopressin is produced by magnocellular neurosecretory neurons in the paraventricular nucleus of hypothalamus (PVN) and supraoptic nucleus (SON). It then travels down the axon through the infundibulum within neurosecretory granules that are found within Herring bodies, localized swellings of the axons and nerve terminals. These carry the peptide directly to the posterior pituitary gland, where it is stored until released into the blood.
There are other sources of AVP, beyond the hypothalamic magnocellular neurons. For example, AVP is also synthesized by parvocellular neurosecretory neurons of the PVN, transported and released at the median eminence, from which it travels through the hypophyseal portal system to the anterior pituitary, where it stimulates corticotropic cells synergistically with CRH to produce ACTH (by itself it is a weak secretagogue). [30]
Vasopressin concentration is used to measure surgical stress for evaluation of surgical techniques. Plasma vasopressin concentration is elevated by noxious stimuli, [31] [32] predominantly during abdominal surgery, [33] [34] [35] especially at gut manipulation, traction of viscera, [36] [37] [38] as well as abdominal insufflation with carbon dioxide during laparoscopic surgery. [39] [40]
Types of AVP receptors and their actions:
Type | Second messenger system | Locations | Actions | Agonists | Antagonists |
---|---|---|---|---|---|
AVPR1A | Phosphatidylinositol/calcium | Liver, kidney, peripheral vasculature, brain | Vasoconstriction, glycogen breakdown, [41] platelet aggregation, and release of factor VIII and von Willebrand factor; social recognition, [42] circadian tau [43] | Felypressin | |
AVPR1B or AVPR3 | Phosphatidylinositol/calcium | Pituitary gland, brain | Adrenocorticotropic hormone secretion in response to stress; [44] social interpretation of olfactory cues [45] | ||
AVPR2 | Adenylate cyclase/cAMP | Basolateral membrane of the cells lining the collecting ducts of the kidneys (especially the cortical and outer medullary collecting ducts) | Insertion of aquaporin-2 (AQP2) channels (water channels). This allows water to be reabsorbed down an osmotic gradient, and so the urine is more concentrated. Release of von Willebrand factor and surface expression of P-selectin through exocytosis of Weibel-Palade bodies from endothelial cells [46] [47] | AVP, desmopressin | "-vaptan" diuretics, i.e. tolvaptan |
The vasopressins are peptides consisting of nine amino acids (nonapeptides). The amino acid sequence of arginine vasopressin (argipressin) is Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH2, with the cysteine residues forming a disulfide bond and the C-terminus of the sequence converted to a primary amide. [48] Lysine vasopressin (lypressin) has a lysine in place of the arginine as the eighth amino acid, and is found in pigs and some related animals, whereas arginine vasopressin is found in humans. [49]
The structure of oxytocin is very similar to that of the vasopressins: It is also a nonapeptide with a disulfide bridge and its amino acid sequence differs at only two positions. The two genes are located on the same chromosome separated by a relatively small distance of less than 15,000 bases in most species. The magnocellular neurons that secrete vasopressin are adjacent to magnocellular neurons that secrete oxytocin, and are similar in many respects. The similarity of the two peptides can cause some cross-reactions: oxytocin has a slight antidiuretic function, and high levels of AVP can cause uterine contractions. [50] [51]
Comparison of vasopressin and oxytocin neuropeptide families:
Vertebrate Vasopressin Family | ||
---|---|---|
Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH2 | Argipressin (AVP, ADH) | Most mammals |
Cys-Tyr-Phe-Gln-Asn-Cys-Pro-Lys-Gly-NH2 | Lypressin (LVP) | Pigs, hippos, warthogs, some marsupials |
Cys-Phe-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH2 | Phenypressin | Some marsupials |
Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Arg-Gly-NH2 | Vasotocin† | Non-mammals |
Vertebrate Oxytocin Family | ||
Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2 | Oxytocin (OXT) | Most mammals, ratfish |
Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Pro-Gly-NH2 | Prol-Oxytocin | Some New World monkeys, northern tree shrews |
Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Ile-Gly-NH2 | Mesotocin | Most marsupials, all birds, reptiles, amphibians, lungfishes, coelacanths |
Cys-Tyr-Ile-Gln-Ser-Cys-Pro-Ile-Gly-NH2 | Seritocin | Frogs |
Cys-Tyr-Ile-Ser-Asn-Cys-Pro-Ile-Gly-NH2 | Isotocin | Bony fishes |
Cys-Tyr-Ile-Ser-Asn-Cys-Pro-Gln-Gly-NH2 | Glumitocin | skates |
Cys-Tyr-Ile-Asn/Gln-Asn-Cys-Pro-Leu/Val-Gly-NH2 | Various tocins | Sharks |
Invertebrate VP/OT Superfamily | ||
Cys-Leu-Ile-Thr-Asn-Cys-Pro-Arg-Gly-NH2 | Inotocin | Locust |
Cys-Phe-Val-Arg-Asn-Cys-Pro-Thr-Gly-NH2 | Annetocin | Earthworm |
Cys-Phe-Ile-Arg-Asn-Cys-Pro-Lys-Gly-NH2 | Lys-Connopressin | Geography & imperial cone snail, pond snail, sea hare, leech |
Cys-Ile-Ile-Arg-Asn-Cys-Pro-Arg-Gly-NH2 | Arg-Connopressin | Striped cone snail |
Cys-Tyr-Phe-Arg-Asn-Cys-Pro-Ile-Gly-NH2 | Cephalotocin | Octopus |
Cys-Phe-Trp-Thr-Ser-Cys-Pro-Ile-Gly-NH2 | Octopressin | Octopus |
†Vasotocin is the evolutionary progenitor of all the vertebrate neurohypophysial hormones. [52] |
Vasopressin is used to manage anti-diuretic hormone deficiency. Vasopressin is used to treat diabetes insipidus related to low levels of antidiuretic hormone. It is available as Pressyn. [53]
Vasopressin has off-label uses and is used in the treatment of vasodilatory shock, gastrointestinal bleeding, ventricular tachycardia and ventricular fibrillation.
Vasopressin agonists are used therapeutically in various conditions, and its long-acting synthetic analogue desmopressin is used in conditions featuring low vasopressin secretion, as well as for control of bleeding (in some forms of von Willebrand disease and in mild haemophilia A) and in extreme cases of bedwetting by children. Terlipressin and related analogues are used as vasoconstrictors in certain conditions. Use of vasopressin analogues for esophageal varices commenced in 1970. [54]
Vasopressin infusions are also used as second line therapy for septic shock patients not responding to fluid resuscitation or infusions of catecholamines (e.g., dopamine or norepinephrine) to increase the blood pressure while sparing the use of catecholamines. These argipressins have much shorter elimination half-life (around 20 minutes) comparing to synthetic non-arginine vasopresines with much longer elimination half-life of many hours. Further, argipressins act on V1a, V1b, and V2 receptors which consequently lead to higher eGFR and lower vascular resistance in the lungs. A number of injectable arginine vasopressins are currently in clinical use in the United States and in Europe.
Vasopressin is administered through an intravenous device, intramuscular injection or a subcutaneous injection. The duration of action depends on the mode of administration and ranges from thirty minutes to two hours. It has a half life of ten to twenty minutes. It is widely distributed throughout the body and remains in the extracellular fluid. It is degraded by the liver and excreted through the kidneys. [53] Arginin vasopressins for use in septic shock are intended for intravenous use only.
The most common side effects during treatment with vasopressin are dizziness, angina, chest pain, abdominal cramps, heartburn, nausea, vomiting, trembling, fever, water intoxication, pounding sensation in the head, diarrhoea, sweating, paleness, and flatulence. The most severe adverse reactions are myocardial infarction and hypersensitivity. [53]
The use of lysine vasopressin is contraindicated in the presence of hypersensitivity to beef or pork proteins, increased BUN and chronic kidney failure. It is recommended that it be cautiously used in instances of perioperative polyuria, sensitivity to the drug, asthma, seizures, heart failure, a comatose state, migraine headaches, and cardiovascular disease. [53]
Decreased AVP release (neurogenic — i.e. due to alcohol intoxication or tumour) or decreased renal sensitivity to AVP (nephrogenic, i.e. by mutation of V2 receptor or AQP) leads to diabetes insipidus, a condition featuring hypernatremia (increased blood sodium concentration), polyuria (excess urine production), and polydipsia (thirst).
Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH) in turn can be caused by a number of problems. Some forms of cancer can cause SIADH, particularly small cell lung carcinoma but also a number of other tumors. A variety of diseases affecting the brain or the lung (infections, bleeding) can be the driver behind SIADH. A number of drugs have been associated with SIADH, such as certain antidepressants (serotonin reuptake inhibitors and tricyclic antidepressants), the anticonvulsant carbamazepine, oxytocin (used to induce and stimulate labor), and the chemotherapy drug vincristine. It has also been associated with fluoroquinolones (including ciprofloxacin and moxifloxacin). [9] Finally, it can occur without a clear explanation. [55] Hyponatremia can be treated pharmaceutically through the use of vasopressin receptor antagonists. [55]
Vasopressin was elucidated and synthesized for the first time by Vincent du Vigneaud.
Evidence for an effect of AVP on monogamy vs polygamy comes from experimental studies in several species, which indicate that the precise distribution of vasopressin and vasopressin receptors in the brain is associated with species-typical patterns of social behavior. In particular, there are consistent differences between monogamous species and polygamous species in the distribution of AVP receptors, and sometimes in the distribution of vasopressin-containing axons, even when closely related species are compared. [56]
Vasopressin has shown nootropic effects on pain perception and cognitive function. [57] Vasopressin also plays a role in autism, major depressive disorder, bipolar disorder, and schizophrenia. [58]
Diabetes insipidus (DI) is a condition characterized by large amounts of dilute urine and increased thirst. The amount of urine produced can be nearly 20 liters per day. Reduction of fluid has little effect on the concentration of the urine. Complications may include dehydration or seizures.
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.
Secretin is a hormone that regulates water homeostasis throughout the body and influences the environment of the duodenum by regulating secretions in the stomach, pancreas, and liver. It is a peptide hormone produced in the S cells of the duodenum, which are located in the intestinal glands. In humans, the secretin peptide is encoded by the SCT gene.
Oxytocin is a peptide hormone and neuropeptide normally produced in the hypothalamus and released by the posterior pituitary. 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. Oxytocin is released into the bloodstream as a hormone in response to sexual activity and during childbirth. 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. 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.
The renin-angiotensin system (RAS), or renin-angiotensin-aldosterone system (RAAS), is a hormone system that regulates blood pressure, fluid, and electrolyte balance, and systemic vascular resistance.
The collecting duct system of the kidney consists of a series of tubules and ducts that physically connect nephrons to a minor calyx or directly to the renal pelvis. The collecting duct participates in electrolyte and fluid balance through reabsorption and excretion, processes regulated by the hormones aldosterone and vasopressin.
Renal physiology is the study of the physiology of the kidney. This encompasses all functions of the kidney, including maintenance of acid-base balance; regulation of fluid balance; regulation of sodium, potassium, and other electrolytes; clearance of toxins; absorption of glucose, amino acids, and other small molecules; regulation of blood pressure; production of various hormones, such as erythropoietin; and activation of vitamin D.
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.
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.
Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue.
The syndrome of inappropriate antidiuretic hormone secretion (SIADH), also known as the syndrome of inappropriate antidiuresis (SIAD), is characterized by a physiologically inappropriate release of antidiuretic hormone (ADH) either from the posterior pituitary gland, or an abnormal non-pituitary source. Unsuppressed ADH causes a physiologically inappropriate increase in solute-free water being reabsorbed by the tubules of the kidney to the venous circulation leading to hypotonic hyponatremia.
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.
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.
Vasopressin receptor 2 (V2R), or arginine vasopressin receptor 2, is a protein that acts as receptor for vasopressin. AVPR2 belongs to the subfamily of G-protein-coupled receptors. Its activity is mediated by the Gs type of G proteins, which stimulate adenylate cyclase.
The actions of vasopressin are mediated by stimulation of tissue-specific G protein-coupled receptors (GPCRs) called vasopressin receptors that are classified into the V1 (V1A), V2, and V3 (V1B) receptor subtypes. These three subtypes differ in localization, function and signal transduction mechanisms.
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.
A vasopressin receptor antagonist (VRA) is an agent that interferes with action at the vasopressin receptors. Most commonly VRAs are used in the treatment of hyponatremia, especially in patients with congestive heart failure, liver cirrhosis or SIADH.
The neurohypophysial hormones form a family of structurally and functionally related peptide hormones. Their representatives in humans are oxytocin and vasopressin. They are named after the location of their release into the blood, the neurohypophysis.
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.