G proteins, also known as guanine nucleotide-binding proteins, are a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior. Their activity is regulated by factors that control their ability to bind to and hydrolyze guanosine triphosphate (GTP) to guanosine diphosphate (GDP). When they are bound to GTP, they are 'on', and, when they are bound to GDP, they are 'off'. G proteins belong to the larger group of enzymes called GTPases.
Sir John Carew Eccles was an Australian neurophysiologist and philosopher who won the 1963 Nobel Prize in Physiology or Medicine for his work on the synapse. He shared the prize with Andrew Huxley and Alan Lloyd Hodgkin.
In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a pea and weighing 0.5 grams (0.018 oz) in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The hypophysis rests upon the hypophysial fossa of the sphenoid bone in the center of the middle cranial fossa and is surrounded by a small bony cavity covered by a dural fold. The anterior pituitary is a lobe of the gland that regulates several physiological processes. The intermediate lobe synthesizes and secretes melanocyte-stimulating hormone. The posterior pituitary is a lobe of the gland that is functionally connected to the hypothalamus by the median eminence via a small tube called the pituitary stalk.
Adrenocorticotropic hormone is a polypeptide tropic hormone produced by and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent. ACTH is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological stress. Its principal effects are increased production and release of cortisol by the cortex of the adrenal gland. ACTH is also related to the circadian rhythm in many organisms.
The hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions. One of the most important functions of the hypothalamus 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. In the terminology of neuroanatomy, it forms the ventral part of the diencephalon. All vertebrate brains contain a hypothalamus. In humans, it is the size of an almond.
Thyrotropin-releasing hormone (TRH) is a hypophysiotropic hormone produced by neurons in the hypothalamus that stimulates the release of thyroid-stimulating hormone (TSH) and prolactin from the anterior pituitary.
A major organ of the endocrine system, the anterior pituitary is the glandular, anterior lobe that together with the posterior lobe makes up the pituitary gland (hypophysis). The anterior pituitary regulates several physiological processes, including stress, growth, reproduction, and lactation. Proper functioning of the anterior pituitary and of the organs it regulates can often be ascertained via blood tests that measure hormone levels.
Walter Rudolf Hess was a Swiss physiologist who won the Nobel Prize in Physiology or Medicine in 1949 for mapping the areas of the brain involved in the control of internal organs. He shared the prize with Egas Moniz.
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.
Gustavus Adolphus College is a private liberal arts college in St. Peter, Minnesota. It was founded in 1862 by Swedish Americans led by Eric Norelius and is affiliated with the Evangelical Lutheran Church in America. Gustavus gets its name from Gustavus Adolphus, the King of Sweden from 1611 to 1632. The college retains its Swedish and Lutheran heritage.
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, 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.
The ventrolateral preoptic nucleus (VLPO), also known as the intermediate nucleus of the preoptic area (IPA), is a small cluster of neurons situated in the anterior hypothalamus, sitting just above and to the side of the optic chiasm in the brain of humans and other animals. The brain's sleep-promoting nuclei, together with the ascending arousal system which includes components in the brainstem, hypothalamus and basal forebrain, are the interconnected neural systems which control states of arousal, sleep, and transitions between these two states. The VLPO is active during sleep, particularly during non-rapid eye movement sleep, and releases inhibitory neurotransmitters, mainly GABA and galanin, which inhibit neurons of the ascending arousal system that are involved in wakefulness and arousal. The VLPO is in turn innervated by neurons from several components of the ascending arousal system. The VLPO is activated by the endogenous sleep-promoting substances adenosine and prostaglandin D2. The VLPO is inhibited during wakefulness by the arousal-inducing neurotransmitters norepinephrine and acetylcholine. The role of the VLPO in sleep and wakefulness, and its association with sleep disorders – particularly insomnia and narcolepsy – is a growing area of neuroscience research.
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.
The Nobel Conference is an academic conference held annually at Gustavus Adolphus College in St. Peter, Minnesota. Founded in 1963, the conference links a general audience with the world's foremost scholars and researchers in conversations centered on contemporary issues related to the natural and social sciences. It is the first ongoing academic conference in the United States to have the official authorization of the Nobel Foundation in Stockholm, Sweden.
The ventromedial nucleus of the hypothalamus is a nucleus of the hypothalamus. "The ventromedial hypothalamus (VMH) is a distinct morphological nucleus involved in terminating hunger, fear, thermoregulation, and sexual activity." This nuclear region is involved with the recognition of the feeling of fullness.
The sexually dimorphic nucleus (SDN) is an ovoid, densely packed cluster of large cells located in the medial preoptic area (POA) of the hypothalamus which is believed to be related to sexual behavior in animals. Thus far, for all species of mammals investigated, the SDN has been repeatedly found to be considerably larger in males than in females. In humans, the volume of the SDN has been found to be 2.2 times as large in males as in females and to contain 2.1 times as many cells. The human SDN is elongated in females and more spherical in males. No sex differences have been observed in the human SDN in either cell density or mean diameter of the cell nuclei. The volume and cell number of the human SDN considerably decreases with age, although the decrease in cell number is both sex and age-specific. In males, a substantial decrease in the cell number of the human SDN was observed between the age of 50–60 years. Cell death was more common in females than males, especially among those older than 70 years of age. The SDN cell number in females can drop to 10-15% of that found in early childhood.
The amygdalofugal pathway is one of the three major efferent pathways of the amygdala, meaning that it is one of the three principal pathways by which fibers leave the amygdala. It leads from the basolateral nucleus and central nucleus of the amygdala. The amygdala is a limbic structure in the medial temporal lobe of the brain. The other main efferent pathways from the amygdala are the stria terminalis and anterior commissure.
The preoptic area is a region of the hypothalamus. MeSH classifies it as part of the anterior hypothalamus. TA lists four nuclei in this region,.
Sham rage is behavior such as biting, clawing, hissing, arching the back and "violent alternating limb movements" produced in animal experiments by removing the cerebral cortex, which are claimed to occur in the absence of any sort of inner experience of rage. These behavioral changes are reversed with small lesions in hypothalamus.
Geoffrey Wingfield Harris (1913–1971) was a British physiologist and neuroendocrinologist. Often considered the "father of neuroendocrinology", he is best known for showing that the anterior pituitary is regulated by the hypothalamus via the hypophyseal portal system. His work established the principles for the 1977 Nobel Prize-winning discovery of hypothalamic hormones by Schally and Guillemin.
