Hormone
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[[Image:Adrenaline chemical structure.png|right|thumb|[[Epinephrine]] (adrenaline), a [[catecholamine]]-type hormone |200px]]
'''Hormones''' (from [[Greek language|Greek]] ''{{Polytonic|}}ὁρμή'' - "impetus") are chemicals released by cells that affect cells in other parts of the body. Only a small amount of hormone is required to alter cell metabolism. It is also a chemical messenger that transports a signal from one cell to another. All [[multicellular organism]]s produce hormones; [[plant]] hormones are also called [[phytohormone]]s. Hormones in [[animal]]s are often transported in the blood. Cells respond to a hormone when they [[gene expression|express]] a specific [[receptor (biochemistry)|receptor]] for that hormone. The hormone binds to the receptor protein, resulting in the activation of a [[signal transduction]] mechanism that ultimately leads to cell type-specific responses.
[[endocrine system|Endocrine]] hormone [[molecule]]s are secreted (released) directly into the [[bloodstream]], while [[exocrine gland|exocrine hormones]] (or ectohormones) are secreted directly into a duct, and from the duct they either flow into the bloodstream or they flow from cell to cell by [[diffusion]] in a process known as [[paracrine signalling]].
==Hierarchical nature of hormonal control==
Hormonal regulation of some physiological activities involves a hierarchy of cell types acting on each other either to stimulate or to modulate the release and action of a particular hormone. The secretion of hormones from successive levels of [[endocrine system| endocrine cell]]s is stimulated by chemical signals originating from cells higher up the hierarchical system. The master coordinator of hormonal activity in [[mammal]]s is the [[hypothalamus]], which acts on input that it receives from the [[central nervous system]].<ref>{{cite book | title=Biochemistry | author=Mathews, CK and van Holde, K. E. | chapter=Integration and control of metabolic processes | editor=Bowen, D. | year=1990 | publisher=The Benjamin/Cummings publishing group | pages=790-792 | id=ISBN 0-8053-5015-2}}</ref>
Other hormone secretion occurs in response to local conditions, such as the rate of secretion of [[parathyroid hormone]] by the [[parathyroid]] cells in response to fluctuations of ionized [[calcium]] levels in [[extracellular fluid]].
==Hormone signaling==
Hormonal signalling across this hierarchy involves the following:
#'''[[Protein biosynthesis|Biosynthesis]]''' of a particular hormone in a particular tissue
#'''Storage and [[Cellular secretion|secretion]]''' of the hormone
#'''Transport''' of the hormone to the target cell(s)
#'''Recognition''' of the hormone by an [[membrane protein| associated cell membrane]] or [[intracellular]] [[receptor (biochemistry)|receptor]] protein.
#'''Relay and amplification''' of the received hormonal signal via a [[signal transduction]] process: This then leads to a cellular response. The reaction of the target cells may then be recognized by the original hormone-producing cells, leading to a [[down-regulation]] in hormone production. This is an example of a [[homeostasis| homeostatic]] [[negative feedback loop]].
#'''Degradation''' of the hormone.
As can be inferred from the hierarchical diagram, hormone biosynthetic cells are typically of a specialized cell type, residing within a particular [[endocrine system| endocrine gland]] (e.g., the [[thyroid gland]], the [[ovary|ovaries]], or the [[testes]]). Hormones may exit their cell of origin via [[exocytosis]] or another means of [[cell membrane|membrane transport]]. However, the hierarchical model is an oversimplification of the hormonal signaling process. Cellular recipients of a particular hormonal signal may be one of several cell types that reside within a number of different tissues, as is the case for [[insulin]], which triggers a diverse range of systemic physiological effects. Different tissue types may also respond differently to the same hormonal signal. Because of this, hormonal signaling is elaborate and hard to dissect.
==Interactions with receptors==
Most hormones initiate a cellular response by initially combining with either a specific [[intracellular]] or [[membrane protein| cell membrane associated]] [[receptor (biochemistry)|receptor]] protein. A cell may have several different receptors that recognize the same hormone and activate different [[signal transduction]] pathways, or alternatively different hormones and their receptors may invoke the same biochemical pathway.
For many hormones, including most [[protein hormone]]s, the receptor is membrane associated and embedded in the [[plasma membrane]] at the surface of the cell. The interaction of hormone and receptor typically triggers a cascade of secondary effects within the [[cytoplasm]] of the cell, often involving [[phosphorylation]] or dephosphorylation of various other cytoplasmic proteins, changes in [[ion channel]] permeability, or increased concentrations of intracellular molecules that may act as [[second messenger| secondary messengers]] (e.g. [[cyclic AMP]]). Some [[protein hormone]]s also interact with [[intracellular]] receptors located in the [[cytoplasm]] or [[Cell nucleus|nucleus]] by an [[intracrine]] mechanism.
For hormones such as [[Steroid hormone|steroid]] or [[Thyroid hormone|thyroid]] hormones, their receptors are located [[intracellular| intracellularly]] within the [[cytoplasm]] of their target cell. In order to bind their receptors these hormones must cross the cell membrane. The combined hormone-receptor [[protein complex| complex]] then moves across the nuclear membrane into the nucleus of the cell, where it binds to specific [[DNA sequences]], effectively amplifying or suppressing the action of certain [[genes]], and affecting [[protein synthesis]].<ref name=beato>{{cite journal | author =Beato M, Chavez S and Truss M | title = Transcriptional regulation by steroid hormones | journal = Steroids | year=1996 | volume=61 | issue=4 | pages=240–251 | pmid = 8733009 | doi = 10.1016/0039-128X(96)00030-X <!--Retrieved from CrossRef by DOI bot-->}}</ref> However, it has been shown that not all steroid receptors are located [[intracellular| intracellularly]], some are [[plasma membrane]] associated.<ref name=hammes>{{cite journal | author =Hammes SR | title = The further redefining of steroid-mediated signaling | journal = Proc Natl Acad Sci USA | year=2003 | volume=100 | issue=5 | pages=21680–2170 | pmid = 12606724 | doi = 10.1073/pnas.0530224100 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
An important consideration, dictating the level at which cellular [[signal transduction]] pathways are activated in response to a hormonal signal is the effective [[concentration]] of hormone-receptor complexes that are formed. Hormone-receptor complex concentrations are effectively determined by three factors:
#The number of hormone molecules available for complex formation
#The number of receptor molecules available for complex formation and
#The [[dissociation constant#protein ligand binding| binding affinity]] between hormone and receptor.
The number of hormone molecules available for complex formation is usually the key factor in determining the level at which [[signal transduction]] pathways are activated. The number of hormone molecules available being determined by the concentration of circulating hormone, which is in turn influenced by the level and rate at which they are secreted by biosynthetic cells. The number of receptors at the cell surface of the receiving cell can also be varied as can the [[dissociation constant#protein ligand binding| affinity]] between the hormone and its receptor.
==Physiology of hormones==
Most cells are capable of producing one or more molecules, which act as signaling molecules to other cells, altering their growth, function, or metabolism. The classical hormones produced by cells in the [[endocrine gland]]s mentioned so far in this article are cellular products, specialized to serve as regulators at the overall organism level. However they may also exert their effects solely within the tissue in which they are produced and originally released.
The rate of hormone biosynthesis and secretion is often regulated by a [[Homeostasis|homeostatic]] [[negative feedback]] control mechanism. Such a mechanism depends on factors which influence the [[metabolism]] and [[excretion]] of hormones. Thus, higher hormone concentration alone can not trigger the negative feedback mechanism. Negative feedback must be triggered by overproduction of an "effect" of the hormone.
Hormone secretion can be stimulated and inhibited by:
*Other hormones (''stimulating''- or ''releasing''-hormones)
*Plasma concentrations of ions or nutrients, as well as binding [[globulin]]s
*[[Neuron]]s and mental activity
*Environmental changes, e.g., of light or temperature
One special group of hormones is the [[tropic hormone]]s that stimulate the hormone production of other [[endocrine system|endocrine glands]]. For example, [[thyroid-stimulating hormone]] (TSH) causes growth and increased activity of another endocrine gland, the [[thyroid]], which increases output of [[thyroid hormone]]s.
A recently-identified class of hormones is that of the "hunger hormones" - [[ghrelin]], [[orexin]] and [[PYY 3-36]] - and "satiety hormones" - e.g., [[leptin]], [[obestatin]], [[nesfatin-1]].
In order to release active hormones quickly into the [[circulation]], hormone biosynthetic cells may produce and store biologically inactive hormones in the form of [[prehormone| pre-]] or [[prohormone| prohormones]]. These can then be quickly converted into their active hormone form in response to a particular stimulus.
==Hormone effects==
Hormone effects vary widely, but can include:
* stimulation or inhibition of growth,
* In puberty hormones can affect [[mood]] and [[mind]]
* induction or suppression of [[apoptosis]] (programmed cell death)
* activation or inhibition of the [[immune system]]
* regulating [[metabolism]]
* preparation for a new activity (e.g., [[fighting]], [[fleeing]], [[mating]])
* preparation for a new phase of life (e.g., [[puberty]], [[caring for offspring]], [[menopause]])
* controlling the [[reproductive cycle]]
In many cases, one hormone may regulate the production and release of other hormones
Many of the responses to hormone signals can be described as serving to [[homeostasis|regulate]] metabolic activity of an organ or tissue.
==Chemical classes of hormones==
[[Vertebrate]] hormones fall into three chemical classes:
* [[Amine]]-derived hormones are derivatives of the [[amino acid]]s [[tyrosine]] and [[tryptophan]]. Examples are [[catecholamine]]s and [[thyroxine]].
* [[Peptide hormone]]s consist of chains of amino acids. Examples of small peptide hormones are [[thyrotropin-releasing hormone|TRH]] and [[vasopressin]]. Peptides composed of scores or hundreds of amino acids are referred to as [[protein]]s. Examples of protein hormones include [[insulin]] and growth hormone. More complex protein hormones bear [[carbohydrate]] side chains and are called [[glycoprotein]] hormones. [[Luteinizing hormone]], [[follicle-stimulating hormone]] and [[thyroid-stimulating hormone]] are glycoprotein hormones.
* [[Lipid]] and [[phospholipid]]-derived hormones derive from lipids such as [[linoleic acid]] and [[arachidonic acid]] and phospholipids. The main classes are the [[steroid hormones]] that derive from [[cholesterol]] and the [[eicosanoid]]s. Examples of [[steroid hormones]] are [[testosterone]] and [[cortisol]]. [[Sterol]] hormones such as [[calcitriol]] are a [[homology (biology)|homologous]] system. The [[adrenal cortex]] and the [[gonad]]s are primary sources of steroid hormones. Examples of [[eicosanoid]]s are the widely studied [[prostaglandin]]s.
==Pharmacology==
Many hormones and their [[analog (chemistry)| analogue]]s are used as [[medication]]. The most commonly-prescribed hormones are [[estrogen]]s and [[progestagen]]s (as methods of [[hormonal contraception]] and as [[Hormone replacement therapy|HRT]]), [[thyroxine]] (as [[levothyroxine]], for [[hypothyroidism]]) and [[steroid]]s (for [[autoimmune disease]]s and several [[pulmonology|respiratory disorders]]). [[Insulin]] is used by many [[diabetes mellitus|diabetics]]. Local preparations for use in [[otolaryngology]] often contain [[pharmacology|pharmacologic]] equivalents of [[adrenaline]], while [[steroid]] and [[vitamin D]] creams are used extensively in [[dermatology|dermatological]] practice.
A "pharmacologic dose" of a hormone is a medical usage referring to an amount of a hormone far greater than naturally occurs in a healthy body. The effects of pharmacologic doses of hormones may be different from responses to naturally-occurring amounts and may be therapeutically useful. An example is the ability of pharmacologic doses of [[glucocorticoid]] to suppress [[inflammation]].
==Important human hormones==
Spelling is not uniform for many hormones. Current North American and international usage is estrogen, gonadotropin, while British usage retains the Greek [[diphthong]] in oestrogen and favors the earlier spelling gonadotrophin (from ''trophē'' ‘nourishment, sustenance’ rather than ''tropē'' ‘turning, change’.
{| class="wikitable" class="sortable wikitable"
| | '''Structure''' || '''Name''' || '''Abbrev- <BR> iation''' || '''Tissue''' || '''Cells''' || '''Mechanism''' || '''Target Tissue''' || '''Effect'''
|-
| amine - tryptophan || [[Melatonin]] (N-acetyl-5-methoxytryptamine) || || [[pineal gland]] || [[pinealocyte]] || || || [[antioxidant]] and causes [[drowsiness]]
|-
| amine - tryptophan || [[Serotonin]] || 5-HT || [[central nervous system|CNS]], [[gastrointestinal tract|GI tract]] || [[enterochromaffin cell]] || || || Controls mood, appetite, and sleep
|-
| amine - tyrosine || [[Thyroxine]] (or tetraiodothyronine) (a [[thyroid hormone]]) || T4 || [[thyroid gland]] || [[thyroid epithelial cell]] || direct || || less active form of [[thyroid hormone]]: increase the [[basal metabolic rate]] & sensitivity to [[catecholamine]]s,
affect [[protein synthesis]]
|-
| amine - tyrosine || [[Triiodothyronine]] (a [[thyroid hormone]]) || T3 || [[thyroid gland]] || [[thyroid epithelial cell]] || direct || || potent form of [[thyroid hormone]]: increase the [[basal metabolic rate]] & sensitivity to [[catecholamine]]s,
affect [[protein synthesis]]
|-
| amine - tyrosine ([[Catecholamine|cat]]) || [[Epinephrine]] (or adrenaline) || EPI || [[adrenal medulla]] || [[chromaffin cell]] || || || [[Fight-or-flight response]]:
Boosts the supply of [[oxygen]] and [[glucose]] to the [[brain]] and [[muscles]] (by increasing [[heart rate]] and [[stroke volume]], [[vasodilation]], increasing [[catalysis]] of [[glycogen]] in liver, breakdown of [[lipid]]s in [[adipocyte|fat cells]].
dilate the [[pupil]]s
Suppress non-emergency bodily processes (e.g. [[digestion]])
Suppress [[immune system]]
|-
| amine - tyrosine ([[Catecholamine|cat]]) || [[Norepinephrine]] (or noradrenaline) || NRE || [[adrenal medulla]]|| [[chromaffin cell]] || || || [[Fight-or-flight response]]:
Boosts the supply of [[oxygen]] and [[glucose]] to the [[brain]] and [[muscles]] (by increasing [[heart rate]] and [[stroke volume]], [[vasoconstriction]] and increased [[blood pressure]], breakdown of [[lipid]]s in [[adipocyte|fat cells]].
Increase [[skeletal muscle]] readiness.
|-
| amine - tyrosine ([[Catecholamine|cat]]) || [[Dopamine]] (or prolactin inhibiting hormone || DPM, PIH or DA || [[kidney]], [[hypothalamus]]|| [[Chromaffin cell]]s in kidney <BR>[[Arcuate nucleus|Dopamine neurons of the arcuate nucleus]] in hypothalamus || || || Increase [[heart]] rate and [[blood pressure]] <BR> Inhibit release of [[prolactin]] and [[Thyrotropin-releasing hormone|TRH]] from [[anterior pituitary]]
|-
| peptide || [[Antimullerian hormone]] (or mullerian inhibiting factor or hormone) || AMH || [[testes]] || [[Sertoli cell]] || || || Inhibit release of [[prolactin]] and [[Thyrotropin-releasing hormone|TRH]] from [[anterior pituitary]]
|-
| peptide || [[Adiponectin]] || Acrp30 || [[adipose tissue]] || || || ||
|-
| peptide || [[Adrenocorticotropic hormone]] (or corticotropin) || ACTH || [[anterior pituitary]] || [[corticotrope]] || cAMP || || synthesis of [[corticosteroid]]s ([[glucocorticoid]]s and [[androgen]]s) in [[Adrenal cortex|adrenocortical cells]]
|-
| peptide || [[Angiotensinogen]] and [[angiotensin]] || AGT || [[liver]] || || IP3 || || [[vasoconstriction]]
release of [[aldosterone]] from [[adrenal cortex]]
[[dipsogen]].
|-
| peptide || [[Antidiuretic hormone]] (or vasopressin, arginine vasopressin) || ADH || [[posterior pituitary]] || [[Paraventricular nucleus of hypothalamus|Parvocellular neurosecretory neurons]] in hypothalamus <BR> [[Magnocellular neurosecretory cell]]s in posterior pituitary || varies || || retention of water in [[kidney]]s <BR> moderate [[vasoconstriction]] <BR> Release [[Adrenocorticotropic hormone|ACTH]] in [[anterior pituitary]]
|-
| peptide || [[Atrial-natriuretic peptide]] (or atriopeptin) || ANP || [[heart]] || || cGMP || ||
|-
| peptide || [[Calcitonin]] || CT || [[thyroid gland]] || [[parafollicular cell]] || cAMP || || Construct bone, reduce blood [[calcium|Ca<sup>2+</sup>]]
|-
| peptide || [[Cholecystokinin]] || CCK || [[duodenum]] || || || || Release of digestive [[enzyme]]s from [[pancreas]]
Release of [[bile]] from [[gallbladder]]
[[hunger]] suppressant
|-
| peptide || [[Corticotropin-releasing hormone]] || CRH || [[hypothalamus]] || || cAMP || || Release [[Adrenocorticotropic hormone|ACTH]] from [[anterior pituitary]]
|-
| peptide || [[Erythropoietin]] || EPO || [[kidney]] || [[Extraglomerular mesangial cell]]s || || || Stimulate [[erythrocyte]] production
|-
| peptide || [[Follicle-stimulating hormone]] || FSH || [[anterior pituitary]] || [[gonadotrope]] || cAMP || || In female: stimulates maturation of [[Graafian follicle]]s in [[ovary]].
In male: [[spermatogenesis]], enhances production of [[androgen-binding protein]] by the [[Sertoli cell]]s of the [[testes]]
|-
| peptide || [[Gastrin]] || GRP || [[stomach]], [[duodenum]] || [[G cell]] || || || Secretion of [[gastric acid]] by [[parietal cell]]s
|-
| peptide || [[Ghrelin]] || || [[stomach]] || [[P/D1 cell]] || || || Stimulate [[appetite]],
secretion of [[growth hormone]] from [[anterior pituitary gland]]
|-
| peptide || [[Glucagon]] || GCG || [[pancreas]] || [[alpha cells]] || cAMP || || [[glycogenolysis]] and [[gluconeogenesis]] in [[liver]]
increases blood glucose level
|-
| peptide || [[Gonadotropin-releasing hormone]] || GnRH || [[hypothalamus]] || || IP3 || || Release of [[Follicle-stimulating hormone|FSH]] and [[Luteinizing hormone|LH]] from [[anterior pituitary]].
|-
| peptide || [[Growth hormone-releasing hormone]] || GHRH || [[hypothalamus]] || || IP3 || || Release [[Growth hormone|GH]] from [[anterior pituitary]]
|-
| peptide || [[Human chorionic gonadotropin]] || hCG || [[placenta]] || [[syncytiotrophoblast]] cells || cAMP || || promote maintenance of [[corpus luteum]] during beginning of [[pregnancy]]
Inhibit [[immune system|immune]] response, towards the [[human embryo]].
|-
| peptide || [[Human placental lactogen]] || HPL || [[placenta]] || || || || increase production of [[insulin]] and [[IGF-1]]
increase [[insulin resistance]] and [[carbohydrate]] intolerance
|-
| peptide || [[Growth hormone]] || GH or hGH || [[anterior pituitary]] || [[somatotrope]]s || || || stimulates [[human development (biology)|growth]] and [[cell (biology)|cell]] reproduction
Release [[Insulin-like growth factor 1]] from [[liver]]
|-
| peptide || [[Inhibin]] || || [[testes]], [[ovary]], [[fetus]] || [[Sertoli cells]] of testes <BR> [[granulosa cells]] of ovary <BR> [[trophoblast]]s in fetus || [[anterior pituitary]] || Inhibit production of [[follicle stimulating hormone|FSH]]
|-
| peptide || [[Insulin]] || INS || [[pancreas]] || [[beta cells]] || [[tyrosine kinase]] || || Intake of [[glucose]], [[glycogenesis]] and [[glycolysis]] in [[liver]] and [[muscle]] from blood
intake of [[lipid]]s and synthesis of [[triglyceride]]s in [[adipocytes]]
Other [[anabolism|anabolic]] effects
|-
| peptide || [[Insulin-like growth factor]] (or somatomedin) || IGF || [[liver]] || [[Hepatocyte]]s || [[tyrosine kinase]] || || insulin-like effects
regulate [[cell growth]] and development
|-
| peptide || [[Leptin]] || LEP || [[adipose tissue]] || || || || decrease of [[appetite]] and increase of [[metabolism]].
|-
| peptide || [[Luteinizing hormone]] || LH || [[anterior pituitary]] || [[gonadotrope]]s || cAMP || || In female: [[ovulation]]
In male: stimulates [[Leydig cell]] production of [[testosterone]]
|-
| peptide || [[Melanocyte stimulating hormone]] || MSH or α-MSH || [[anterior pituitary]]/[[pars intermedia]] || [[Melanotroph]] || cAMP || || [[melanogenesis]] by [[melanocyte]]s in [[skin]] and [[hair]]
|-
| peptide || [[Orexin]] || || [[hypothalamus]] || || || || wakefulness and increased energy expenditure, increased appetite
|-
| peptide || [[Oxytocin]] || OXT || [[posterior pituitary]] || [[Magnocellular neurosecretory cell]]s || IP3 || || release breast milk
Contraction of [[cervix]] and [[vagina]]
Involved in [[orgasm]], trust between people.<ref>Kosfeld M ''et al.'' (2005) Oxytocin increases trust in humans. ''[[Nature (journal)|Nature]]'' 435:673-676. [http://www.iew.unizh.ch/home/kosfeld/papers/ottrust_nature.pdf PDF] PMID 15931222</ref> and [[Circadian#Animal circadian rhythms|circadian homeostasis]] (body temperature, activity level, wakefulness) <ref>[http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=C001082B-2B35-221B-641CA6ED64E8BCF3 Scientific American Mind, "Rhythm and Blues"; June/July 2007; Scientific American Mind; by Ulrich Kraft]</ref>.
|-
| peptide || [[Parathyroid hormone]] || PTH || [[parathyroid gland]] || [[parathyroid chief cell]] || cAMP || || increase blood [[calcium|Ca<sup>2+</sup>]]: *indirectly stimulate [[osteoclast]]s
* Ca<sup>2+</sup> reabsorption in [[kidney]]
* activate [[vitamin D]]
(Slightly) decrease blood [[phosphate]]:
* (decreased reuptake in [[kidney]] but increased uptake from bones
* activate [[vitamin D]])
|-
| peptide || [[Prolactin]] || PRL || [[anterior pituitary]], [[uterus]] || [[lactotroph]]s of anterior pituitary <BR> [[Decidual cells]] of uterus || || || milk production in [[mammary glands]] <BR> [[orgasm|sexual gratification]] after [[Human sexual behavior|sexual acts]]
|-
| peptide || [[Relaxin]] || RLN || [[uterus]] || [[Decidual cells]] || || || Unclear in humans
|-
| peptide || [[Secretin]] || SCT || [[duodenum]] || [[S cell]] || || || Secretion of [[bicarbonate]] from [[liver]], [[pancreas]] and duodenal [[Brunner's gland]]s
Enhances effects of [[cholecystokinin]]
Stops production of gastric juice
|-
| peptide || [[Somatostatin]] || SRIF || [[hypothalamus]], [[islets of Langerhans]], [[gastrointestinal system]] || [[delta cell]]s in islets <BR> Neuroendocrince cells of the [[Periventricular nucleus]] in hypothalamus || || || Inhibit release of [[Growth hormone|GH]] and [[Thyrotropin-releasing hormone|TRH]] from [[anterior pituitary]] <BR> Suppress release of [[gastrin]], [[cholecystokinin]] (CCK), [[secretin]], [[motilin]], [[vasoactive intestinal peptide]] (VIP), [[gastric inhibitory polypeptide]] (GIP), [[enteroglucagon]] in [[gastrointestinal system]] <BR> Lowers rate of gastric emptying
Reduces [[smooth muscle]] contractions and blood flow within the intestine <ref name="Colorado"> http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/otherendo/somatostatin.html Colorado State University - Biomedical Hypertextbooks - Somatostatin </ref> <BR> Inhibit release of [[insulin]] from [[beta cells]] <ref name="GP5417">{{GeorgiaPhysiology|5/5ch4/s5ch4_17}}</ref> <BR> Inhibit release of [[glucagon]] from [[beta cells]] <ref name="GP5417" /> <BR> Suppress the exocrine secretory action of [[pancreas]].
|-
| peptide || [[Thrombopoietin]] || TPO || [[liver]], [[kidney]], [[striated muscle]] || [[Myocyte]]s || || [[megakaryocyte]]s || produce [[platelets]]<ref name=Kaushansky2006>Kaushansky K. Lineage-specific hematopoietic growth factors. ''[[N Engl J Med]]'' 2006;354:2034-45. PMID 16687716.</ref>
|-
| peptide || [[Thyroid-stimulating hormone]] (or thyrotropin) || TSH || [[anterior pituitary]] || [[thyrotrope]]s || cAMP || [[thyroid gland]] || secrete [[thyroxine]] (T4) and [[triiodothyronine]] (T3)
|-
| peptide || [[Thyrotropin-releasing hormone]] || TRH || [[hypothalamus]] || [[Paraventricular nucleus of hypothalamus|Parvocellular neurosecretory neurons]] || IP3 || [[anterior pituitary]] || Release [[thyroid-stimulating hormone]] (primarily) <BR> Stimulate [[prolactin]] release
|-
| steroid - [[glucocorticoid|glu.]] || [[Cortisol]] || || [[adrenal cortex]] ([[zona fasciculata]] and [[zona reticularis]] cells) || || direct || || Stimulation of [[gluconeogenesis]]
Inhibition of glucose uptake in muscle and [[adipose]] tissue
Mobilization of [[amino acids]] from [[Wiktionary:extrahepatic|extrahepatic]] tissues
Stimulation of [[fat breakdown]] in adipose tissue
[[anti-inflammatory]] and [[immunosuppressive]]
|-
| steroid - [[mineralocorticoid|min.]] || [[Aldosterone]] || || [[adrenal cortex]] ([[zona glomerulosa]]) || || direct || || Increase [[blood volume]] by reabsorption of [[sodium]] in [[kidneys]] (primarily)
[[Potassium]] and [[Hydrogen ion|H<sup>+</sup>]] secretion in kidney.
|-
| steroid - sex ([[androgen|and]]) || [[Testosterone]] || || [[testes]] || [[Leydig cell]]s || direct || || [[Anabolic]]: growth of [[muscle mass]] and strength, increased [[bone density]], growth and strength,
[[Virilizing]]: [[maturation]] of [[sex organs]], formation of [[scrotum]], deepening of voice, growth of [[beard]] and [[axillary hair]].
|-
| steroid - sex ([[androgen|and]]) || [[Dehydroepiandrosterone]] || DHEA || [[testes]], [[ovary]], [[kidney]] || [[Zona fasciculata]] and [[Zona reticularis]] cells of kidney <BR>[[theca cells]] of ovary <BR> [[Leydig cells]]s of testes || direct || || [[Virilization]], [[anabolic]]
|-
| steroid - sex ([[androgen|and]]) || [[Androstenedione]] || || [[adrenal glands]], [[gonads]] || || direct || || Substrate for [[estrogen]]
|-
| steroid - sex ([[androgen|and]]) || [[Dihydrotestosterone]] || DHT || multiple || || direct || ||
|-
| steroid - sex ([[estrogen|est]]) || [[Estradiol]] || E2 || females: [[ovary]], males [[testes]] || females: [[granulosa cells]], males: [[Sertoli cell]] || direct || || '''Females''':
Structural:
* promote formation of female [[secondary sex characteristics]]
* accelerate [[height]] growth
* accelerate [[metabolism]] (burn fat)
* reduce [[muscle]] mass
* stimulate [[endometrium|endometrial]] growth
* increase [[uterus|uterine]] growth
* maintenance of [[blood vessel]]s and skin
* reduce [[bone resorption]], increase bone formation
[[Protein]] synthesis:
* increase hepatic production of binding proteins
[[Coagulation]]:
* increase circulating level of [[coagulation factor|factors]] [[factor II|2]], [[factor VII|7]], [[factor IX|9]], [[factor X|10]], [[antithrombin]] III, [[plasminogen]]
* increase [[platelet]] adhesiveness
Increase [[high density lipoprotein|HDL]], [[triglyceride]], [[height]] growth
Decrease [[low density lipoprotein|LDL]], [[fat]] deposition
Fluid balance:
* salt ([[sodium]]) and water retention
* increase [[growth hormone]]
* increase [[cortisol]], [[SHBG]]
Gastrointestinal tract:
* reduce bowel motility
* increase cholesterol in [[bile]]
Melanin:
* increase [[pheomelanin]], reduce [[eumelanin]]
Cancer: support [[hormone-sensitive]] [[breast cancer]]s <ref>[http://www.breastcancer.org/tre_sys_hrt_idx.html Hormonal Therapy<!-- Bot generated title -->]</ref> Suppression of production in the body of estrogen is a treatment for these cancers.
Lung function:
*promote lung function by supporting [[alveoli]]<ref>{{cite journal | author=Massaro D, Massaro GD | title=Estrogen regulates pulmonary alveolar formation, loss, and regeneration in mice | journal=American Journal of Physiology. Lung Cellular and Molecular Physiology | volume=287 | issue=6 | year=2004 | pages=L1154–9 | pmid=15298854 url=http://ajplung.physiology.org/cgi/content/full/287/6/L1154 | doi=10.1152/ajplung.00228.2004 }}</ref>.
'''Males''': Prevent [[apoptosis]] of germ cells<ref>Pentikäinen V, Erkkilä K, Suomalainen L, Parvinen M, Dunkel L. Estradiol Acts as a Germ Cell Survival Factor in the Human Testis ''in vitro''.
The Journal of Clinical Endocrinology & Metabolism 2006;85:2057-67 PMID 10843196</ref>
|-
| steroid - sex ([[estrogen|est]]) || [[Estrone]] || || [[ovary]] || [[granulosa cells]], [[Adipocyte]]s || direct || ||
|-
| steroid - sex ([[estriol|est]]) || [[Estriol]] || || [[placenta]] || [[syncytiotrophoblast]] || direct || ||
|-
| steroid - sex ([[Progestagen|pro]]) || [[Progesterone]] || || [[ovary]], [[adrenal glands]], [[placenta]] (when pregnant) || [[Granulosa cells]] [[Theca interna|theca cells]] of ovary || direct || || Support [[pregnancy]]<ref name="colostate">[http://www.vivo.colostate.edu/hbooks/pathphys/reprod/placenta/endocrine.html Placental Hormones<!-- Bot generated title -->]</ref>:
Convert [[uterine lining|endometrium]] to secretory stage
Make [[Cervix#Cervical mucus|cervical mucus]] permeable to sperm.
Inhibit [[immune system|immune]] response, e.g. towards the [[human embryo]].
Decrease uterine [[smooth muscle]] contractility<ref name="colostate" />
Inhibit [[lactation]]
Inhibit onset of [[labor (childbirth)|labor]].
Support [[fetal]] production of [[adrenal]] mineralo- and glucosteroids.
Other:
Raise [[epidermal growth factor-1]] levels
Increase core temperature during ovulation<ref name="GeorgiaPhysiology">{{GeorgiaPhysiology|5/5ch9/s5ch9_13}}</ref>
Reduce [[spasm]] and relax [[smooth muscle]] (widen [[bronchi]] and regulate [[mucus]])
[[Inflammation|Antiinflammatory]]
Reduce [[gall-bladder]] activity<ref>{{cite journal |author=Hould F, Fried G, Fazekas A, Tremblay S, Mersereau W |title=Progesterone receptors regulate gallbladder motility |journal=J Surg Res |volume=45 |issue=6 |pages=505–12 |year=1988 |pmid=3184927 | doi = 10.1016/0022-4804(88)90137-0 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
Normalize [[blood]] clotting and vascular tone, [[zinc]] and [[copper]] levels, [[cell (biology)|cell]] [[oxygen]] levels, and use of fat stores for energy.
Assist in [[thyroid]] function and [[bone]] growth by [[osteoblast]]s
[[Relsilience]] in [[bone]], [[teeth]], [[gingiva|gum]]s, [[joint]], [[tendon]], [[ligament]] and [[skin]] Healing by regulating [[collagen]]
Nerve function and healing by regulating [[myelin]]
Prevent [[endometrial cancer]] by regulating effects of estrogen.
|-
| sterol || [[Calcitriol]] (1,25-dihydroxyvitamin D<sub>3</sub>) || || [[skin]]/[[proximal tubule]] of [[kidneys]] || || direct || || Active form of [[vitamin D3]]
Increase absorption of [[calcium]] and [[phosphate]] from [[gastrointestinal tract]] and [[kidneys]]
inhibit release of [[parathyroid hormone|PTH]]
|-
| sterol || [[Calcidiol]] (25-hydroxyvitamin D<sub>3</sub>) || || [[skin]]/[[proximal tubule]] of [[kidneys]] || || direct || || Inactive form of [[Vitamin D3]]
|-
| eicosanoid || [[Prostaglandin]]s || PG || [[seminal vesicle]] || || || ||
|-
| eicosanoid || [[Leukotriene]]s || LT || || [[white blood cells]] || || ||
|-
| eicosanoid || [[Prostacyclin]] || PGI2 || [[endothelium]] || || || ||
|-
| eicosanoid || [[Thromboxane]] || TXA2 || || [[platelets]] || || ||
|-
| || [[Prolactin releasing hormone]]|| PRH || [[hypothalamus]] || || || || Release [[prolactin]] from [[anterior pituitary]]
|-
| || [[Lipotropin]] || PRH || [[anterior pituitary]] || [[Corticotrope]]s || || || [[lipolysis]] and [[steroidogenesis]], <BR> stimulates [[melanocytes]] to produce [[melanin]]
|-
| || [[Brain natriuretic peptide]] || BNP || [[heart]] || [[Cardiac muscle|Cardiac myocytes]] || || || (To a minor degree than ANP) reduce [[blood pressure]] by:
reducing [[systemic circulation|systemic]] [[vascular resistance]],
reducing blood water, sodium and [[blood fats|fats]]
|-
| || [[Neuropeptide Y]] || NPY || [[Stomach]] || || || || increased food intake and decreased physical activity
|-
| || [[Histamine]] || || [[Stomach]] || [[ECL cell]]s || || || stimulate [[gastric acid]] secretion
|-
| || [[Endothelin]] || || [[Stomach]] || [[X cell]]s || || || [[Smooth muscle]] contraction of stomach <ref>[http://www.jstage.jst.go.jp/article/jsmr/41/1/41_35/_article Diabetes-related changes in contractile responses of stomach fundus to endothelin-1 in streptozotocin-induced diabetic rats] Journal of Smooth Muscle Research Vol. 41 (2005) , No. 1 35-47. Kazuki Endo1), Takayuki Matsumoto1), Tsuneo Kobayashi1), Yutaka Kasuya1) and Katsuo Kamata1) </ref>
|-
| || [[Pancreatic polypeptide]] || || [[Pancreas]] || [[PP cell]]s || || || Unknown
|-
| || [[Renin]] || || [[Kidney]] || [[Juxtaglomerular cell]]s|| || || Activates the [[renin-angiotensin system]] by producing [[angiotensin I]] of [[angiotensinogen]]
|-
| || [[Enkephalin]] || || [[Kidney]] || [[Chromaffin cell]]s || || || Regulate pain
|-
|}
==References==
{{Refimprove|date=November 2007}}
{{Reflist}}
==See also==
<div style="-moz-column-count:3; column-count:3;">
* [[Endocrinology]]
* [[Endocrine system]]
* [[Neuroendocrinology]]
* [[Plant hormones]] or [[plant growth regulators]]
* [[Autocrine signaling]]
* [[Paracrine signaling]]
* [[Intracrine]]
* [[Cytokine]]
* [[Growth factor]]
* [[Hormone disruptor]]
</div>
==External links==
* [http://www.hormone.org The Hormone Foundation]
* {{MeshName|Hormones}}
* [http://video.google.com/videoplay?docid=2730429945740914542&q=living+smart%3A+Hormones+and+Nutrition&hl=en Hormones and Nutrition]
{{Hormones}}
[[Category:Hormones|*]]
[[Category:Physiology]]
[[Category:Endocrinology]]
[[Category:Cell signaling]]
[[Category:Signal transduction]]
[[ar:هرمون]]
[[bs:Hormon]]
[[bg:Хормон]]
[[ca:Hormona]]
[[cs:Hormon]]
[[da:Hormon]]
[[de:Hormon]]
[[el:Ορμόνη]]
[[es:Hormona]]
[[eo:Hormono]]
[[fa:هورمون]]
[[fr:Hormone]]
[[ko:호르몬]]
[[hr:Hormoni]]
[[io:Hormono]]
[[id:Hormon]]
[[is:Hormón]]
[[it:Ormone]]
[[he:הורמון]]
[[pam:Hormone]]
[[ka:ჰორმონი]]
[[ku:Hormon]]
[[la:Hormon]]
[[lv:Hormoni]]
[[lt:Hormonas]]
[[hu:Hormon]]
[[mk:Хормони]]
[[ms:Hormon]]
[[nl:Hormoon]]
[[ja:ホルモン]]
[[no:Hormon]]
[[nn:Hormon]]
[[oc:Ormona]]
[[pl:Hormon]]
[[pt:Hormona]]
[[ro:Hormon]]
[[ru:Гормоны]]
[[simple:Hormone]]
[[sq:Hormonet]]
[[sk:Hormón]]
[[sl:Hormon]]
[[sr:Хормони]]
[[su:Hormon]]
[[fi:Hormoni]]
[[sv:Hormon]]
[[ta:வளரூக்கி]]
[[th:ฮอร์โมน]]
[[tg:Ҳормон]]
[[tr:Hormon]]
[[uk:Гормон]]
[[ur:Hormone]]
[[yi:הארמאן]]
[[zh:激素]]