Neuroendocrinology is the study of the interactions between the nervous system and the endocrine system. The concept arose from the recognition that the secretion of hormones from the pituitary gland was closely controlled by the brain, and especially by the hypothalamus. The nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. ... Major endocrine glands. ... Hormone is also the NATO reporting name for the Soviet/Russian Kamov Ka-25 military helicopter. ... The pituitary gland, or hypophysis, is an endocrine gland about the size of a pea that sits in the small, bony cavity (sella turcica) at the base of the brain. ... In the anatomy of mammals, the hypothalamus is a region of the brain located below the thalamus, forming the major portion of the ventral region of the diencephalon and functioning to regulate certain metabolic processes and other autonomic activities. ...

Pioneers of neuroendocrinology

Geoffrey Wingfield Harris (1913-1971) is considered by many to be the 'mother' of Neuroendocrinology. Geoffrey Harris is credited as showing that the anterior pituitary gland of mammals is regulated by factors secreted by hypothalamic neurons into the hypothalamo-hypophysial portal circulation. By contrast, the hormones of the posterior pituitary gland are secreted into the systemic circulation directly from the nerve endings of hypothalamic neurons.

The first of these factors to be identified were thyrotropin-releasing hormone (TRH) and gonadotropin releasing hormone (GnRH). TRH is a small peptide that stimulates the secretion of thyroid stimulating hormone (TSH); GnRH (also called luteinising hormone releasing hormone, LHRH) stimulates the secretion of luteinizing hormone and follicle stimulating hormone (FSH). Thyrotropin-releasing hormone (TRH), also called thyrotropin-releasing factor (TRF) or protirelin, is a tripeptide hormone that stimulates the release of thyroid-stimulating hormone and prolactin by the anterior pituitary. ... Gonadotropin Releasing Hormone (GnRH) is a peptide hormone responsible for the release of FSH and LH from the anterior pituitary. ... Thyroid-stimulating hormone (also known as TSH or thyrotropin) is a hormone produced by thyrotrope cells in the anterior pituitary gland which regulates the endocrine function of the thyroid gland. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Follicle stimulating hormone (FSH) is a hormone produced by gonadotropes in the anterior pituitary gland. ...

Roger Guillemin and Andrew W. Schally isolated these factors from the hypothalamus of sheep and pigs, and then identified their structures. Guillemin and Schally were awarded the Nobel Prize in Physiology and Medicine in 1977 for their contributions to understanding "the peptide hormone production of the brain." Roger Guillemin ( born January 11, 1924 in Dijon, France) is a neuroendocrinologist who received the Nobel prize for Medicine in 1977 for his work on neurohormones. ... Andrzej Wiktor Schally, also known as Andrew W. Schally, (born November 20, 1926) in Wilno, Poland), is a Polish-born endocrinologist and Nobel Prize winner in 1977 in Medicine for research work. ...

Neuroendocrine systems of the hypothalamus

Oxytocin and vasopressin, the two peptide hormones of the posterior pituitary gland (the neurohypophysis), are secreted from the nerve endings of magnocellular neurosecretory neurons into the systemic circulation. The cell bodies of these oxytocin and vasopressin neurons are in the supraoptic nucleus and the paraventricular nucleus, and the electrical activity of these neurons is regulated by afferent synaptic inputs from other brain regions. By contrast, the hormones of the anterior pituitary gland (the adenohypophysis) are secreted from endocrine cells that, in mammals, are not directly innervated, yet the secretion of these hormones (adrenocorticotrophic hormone (ACTH), luteinizing hormone (LH), follicle stimulating hormone (FSH), thyroid stimulating hormone (TSH), prolactin and growth hormone) remains under the control of the brain. The brain controls the anterior pituitary gland by “releasing factors” and “release-inhibiting factors”; these are blood-borne substances released by hypothalamic neurons into blood vessels at the base of the brain, at the median eminence. These vessels, the hypothalamo-hypophysial portal vessels, carry the hypothalamic factors to the adenohypophysis where they bind to specific receptors on the surface of the hormone-producing cells. Oxytocin is a hormone, found in mammals, which in humans is released mainly after stimulation of the nipples or distention of the vagina and which facilitates birth and breastfeeding. ... Arginine vasopressin (AVP), also known as argipressin or antidiuretic hormone (ADH), is a human hormone that is mainly released when the body is low on water; it causes the kidneys to conserve water by concentrating the urine and reducing urine volume. ... The posterior pituitary (also called the neurohypophysis) comprises the posterior lobe of the pituitary gland and is part of the endocrine system. ... The supraoptic nucleus (SON) is a nucleus of magnocellular neurosecretory cells in the hypothalamus of the mammalian brain. ... The paraventricular nucleus (PVN) is an aggregation of neurons in the hypothalamus, adjacent to the third ventricle. ... The anterior pituitary (also called the adenohypophysis) comprises the anterior lobe of the pituitary gland and is part of the endocrine system. ... Adrenocorticotropic hormone (ACTH or corticotropin) is a polypeptide hormone secreted from corticotropes in the anterior lobe of the pituitary gland in response to corticotropin-releasing hormone (CRH) released by the hypothalamus. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Follicle stimulating hormone (FSH) is a hormone produced by gonadotropes in the anterior pituitary gland. ... Thyroid-stimulating hormone (also known as TSH or thyrotropin) is a hormone produced by thyrotrope cells in the anterior pituitary gland which regulates the endocrine function of the thyroid gland. ... Prolactin is a peptide hormone synthesised and secreted by lactotrope cells in the adenohypophysis (anterior pituitary gland). ... Growth hormone Growth hormone is a polypeptide hormone synthesised and secreted by the anterior pituitary gland which stimulates growth and cell reproduction in humans and other vertebrate animals. ... Median Eminence The median eminence is part of the inferior boundary for the hypothalamus. ...

For example, the secretion of growth hormone is controlled by two neuroendocrine systems: the growth hormone releasing hormone (GHRH) neurons and the somatostatin neurons, which stimulate and inhibit GH secretion respectively. The GHRH neurones are located in the arcuate nucleus of the hypothalamus, while the somatostatin cells involved in growth hormone regulation are in the periventricular nucleus. These two neuronal systems project axons to the median eminence where they release their peptides into portal blood vessels for transport to the anterior pituitary. Growth hormone is secreted in pulses, which arise from alternating episodes of GHRH release and somatostatin release, which may reflect neuronal interactions between the GHRH and somatostatin cells, and negative feedback from growth hormone. Growth hormone-releasing hormone (GHRH), also known as growth hormone-releasing factor (GRF or GHRF), is a 44-amino acid peptide hormone produced in the arcuate nucleus of the hypothalamus. ... Somatostatin is a hormone. ... The arcuate nucleus is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. ... Peptides are the family of molecules formed from the linking, in a defined order, of various amino acids. ...

So why are these systems of interest to physiologists and neuroscientists? Firstly, neuroendocrine systems regulate things that matter to most of us. They control reproduction in all its aspects, from bonding to sexual behavior, they control spermatogenesis and the ovarian cycle, parturition, lactation and maternal behaviour. They control the way we respond to stress and infection. They regulate our metabolism – they influence our eating and drinking behaviour, and influence how the energy intake is utilised – i.e. how fat we get. They influence our mood. They regulate body fluid and electrolyte homeostasis, and blood pressure. In other words, these are systems of central importance to many problems that are major health concerns, as well of sometimes of intimate personal interest. Spermatogenesis: the process by which stem cells develop into mature spermatozoa. ... Childbirth in a hospital. ... Kittens nursing Lactation describes the secretion of milk from the mammary glands, the process of providing that milk to the young, and the period of time that a mother lactates to feed her young. ... The factual accuracy of this article is disputed. ... Infection is also the title of an episode of the television series Babylon 5, and the English title of the Japanese film Kansen. ... Santorio Santorio (1561-1636) in his steelyard balance, from Ars de statica medecina, first published 1614 Metabolism (from μεταβολισμος (metabolismos)) is the biochemical modification of chemical compounds in living organisms anggjgjhnd cell (b). ... Blood pressure is the pressure exerted by the blood on the walls of the blood vessels. ...

Secondly, these neurons are large; they are mini “ factories” for producing secretory products; their nerve terminal are large and organised in coherent terminal fields; their output can often be measured easily in the blood; and what these neurons do and what stimuli they respond to are readily open to hypothesis and experiment. For these reasons and more, neuroendocrine neurons are good "model systems" for studying general questions, like “how does a neurone regulate the synthesis, packaging and secretion of its product?” and “how is information encoded in electrical activity?”

The scope of neuroendocrinology

Today, neuroendocrinology embraces a wide range of topics that arose directly or indirectly from the core concept of neuroendocrine neurons. Neuroendocrine neurones control the gonads – and gonadal steroids in turn influence the brain; and so do corticosteroids secreted from the adrenal gland under the influence of ACTH. The study of these feedbacks became naturally the province of neuroendocrinologists. The peptides secreted by hypothalamic neuroendocrine neurons into the blood proved to be released also into the brain, and the central actions often appeared to complement the peripheral actions, so understanding these central actions also became the province of neuroendocrinologists, sometimes even when these peptides cropped up in quite different parts of the brain apparently serving functions unrelated to endocrine regulation. Neuroendocrine neurons were discovered in the peripheral nervous system, regulating for instance digestion. The cells in the adrenal medulla that release adrenaline and noradrenaline proved to have properties between endocrine cells and neurons, and proved to be outstanding model systems for instance for the study of the molecular mechanisms of exocytosis, and these too have become, by extension, “neuroendocrine” systems. In chemistry and biology, Steroids are a type of lipid, characterized by a carbon skeleton with four fused rings. ... In physiology, corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. ... Grays Fig. ... Digestion is the process whereby a biological entity processes a substance, in order to chemically convert the substance into nutrients. ... In mammals, the adrenal glands are the triangle-shaped endocrine glands that sit atop the kidneys. ... Epinephrine (INN) or adrenaline (BAN) is a hormone and a neurotransmitter. ... Norepinephrine, known as noradrenaline outside the USA, is a catecholamine and a phenethylamine with chemical formula C8H11NO3. ... Exocytosis is the process by which a cell is able to get rid of large molecules or materials including wastes through its membrane. ...

Neuroendocrine systems have been important to our understanding of many basic principles in neuroscience and physiology – for instance our understanding of stimulus-secretion coupling. The origins and significance of patterning in neuroendocrine secretion are still dominant themes in neuroendocrinology today. Neuroscience is a field of study that deals with the structure, function, development, genetics, biochemistry, physiology, pharmacology, and pathology of the nervous system, consisting of the myriad nerve pathways running throughout the body. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ...

External links

Neuroendocrine societies

• The International Neuroendocrine Federation
• The American Neuroendocrine Society
• The British Society for Neuroendocrinology
• La Societe de Neuroendocrinologie
• The European Neuroendocrine Association
• The Japan Neuroendocrine Society

Neuroendocrine journals

• 'The Journal of Neuroendocrinology' (Blackwell)
• 'Neuroendocrinology' (Karger)
• 'Frontiers in Neuroendocrinology' (Academic Press)
• 'Hormones and Behavior' (Academic Press)
• 'Neuroendocrinology Letters' (Maghira and Maas Publications)