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Common Vertebrate Hormones












Hormone Structure Functions
Skeletal Muscle Hormones
Irisin 22kDa proteolytic fragment of the transmembrane protein FNDC5 (fibronectin type III domain-containing protein 5) expression induced, in skeletal muscle, by PGC1-α in response to exercise, induces a conversion of white adipose tissue (WAT) into a more brown fat (BAT) type, generally referred to as beige or brite fat cells
Pituitary Hormones
Oxytocin posterior pituitary peptide; polypeptide of 9 amino acids CYIQNCPLG (C's are disulfide bonded) uterine contraction, causes milk ejection in lactating females (the "let-down" response), responds to suckling reflex and estradiol, lowers steroid synthesis in testes
(antidiuretic hormone, ADH)
posterior pituitary peptide; polypeptide of 9 amino acids CYFQNCPRG (C's are disulfide bonded) responds to osmoreceptor which senses extracellular [Na+], blood pressure regulation, increases H2O readsorption from distal tubules in kidney, loss results in dilute urine and polydipsia (constant thirst) condition termed diabetes insipidus
Melanocyte-stimulating hormones (MSH) anterior pituitary peptides derived from POMC:

α polypeptide = 13 amino acids
β polypeptide = 18 amino acids
γ polypeptide = 12 amino acids
α-MSH most significant, involved in control of appetite and feeding behaviors via melanocortin receptor (MC4R)-expressing neurons in hypothalamus, immunomodulation via MC1R-expressing monocytes, macrophages, and dendritic cells (DCs), down-regulates the production of proinflammatory and immunomodulating cytokines (IL-1, IL-6, TNF-α, IL-2, IFN-γ, IL-4, IL-13) as well as the expression of costimulatory molecules (CD86, CD40, ICAM-1) on antigen-presenting DCs
Adrenocorticotropic hormone (ACTH) also called corticotropin anterior pituitary peptide derived from POMC; polypeptide = 39 amino acids stimulates cells of adrenal gland to increase steroid synthesis and secretion
Lipotropin (LPH) anterior pituitary peptides derived from POMC:

β polypeptide = 93 amino acids
γ polypeptide = 60 amino acids
increases fatty acid release from adipocytes
Thyrotropin (thyroid-stimulating hormone, TSH) anterior pituitary peptides; 2 proteins: α is 96 amino acids; β is 112 acts on thyroid follicle cells to stimulate throid hormone synthesis
Growth hormone (GH, or somatotropin) anterior pituitary peptide; protein of 191 amino acids general anabolic stimulant, increases release of insulin-like growth factor-I (IGF-I), cell growth and bone sulfation
Prolactin (PRL) anterior pituitary peptide; protein of 197 amino acids stimulates differentiation of secretory cells of mammary gland and stimulates milk synthesis
Luteinizing hormone (LH); human chorionic gonadotropin (hCG) is similar and produced in placenta anterior pituitary peptides; 2 proteins: α is 96 amino acids; β is 121 increases ovarian progesterone synthesis, luteinization; acts on Leydig cells of testes to increase testosterone synthesis and release and increases interstitial cell development
Follicle-stimulating hormone (FSH) anterior pituitary peptides; 2 proteins: α is 96 amino acids; β is 120 ovarian follicle development and ovulation, increases estrogen production; acts on Sertoli cells of semiferous tubule to increase spermatogenesis
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Hypothalamic Hormones & Peptides

Orexins 2 peptides from single preproprotein; orexin A is 33 amino acids, orexin B is 28 amino acids important roles in the emotional and motivational aspects of feeding behavior, increases food consumption (orexigenic) hence derivation of peptide name; increases wakefulness and suppresses REM sleep
Melanin-concentrating hormone, MCH 19 amino acid cyclic peptide important orexigenic (appetite stimulating) hormone
Neuropeptide Y, NPY 36 amino acids, 5 receptors termed Y receptors effects on hypothalamic function in appetite, controls feeding behavior and energy homeostasis, levels increase during starvation to induce food intake
Corticotropin-releasing factor (CRF or CRH) protein of 41 amino acids acts on corticotrope to release ACTH and β-endorphin (lipotropin)
Gonadotropin-releasing factor (GnRF or GnRH) polypeptide of 10 amino acids acts on gonadotrope to release LH and FSH
Prolactin-releasing factor (PRF) this may be TRH acts on lactotrope to release prolactin
Prolactin-release inhibiting factor (PIF or PIH) is the neurotransmitter dopamine acts on lactotrope to inhibit prolactin release
Growth hormone-releasing factor (GHRF or GHRH) protein of 40 and 44 amino acids stimulates GH secretion
Somatostatin (SIF, also called growth hormone-release inhibiting factor, GHIF) polypeptide of 14 and 28 amino acids inhibits GH and TSH secretion
Thyrotropin-releasing factor (TRH or TRF) peptide of 3 amino acids: EHP stimulates TSH and prolactin secretion
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Thyroid Hormones
Thyroxine and triiodothyronine iodinated dityrosine derivatives responds to TSH and stimulates oxidations in many cells
Calcitonin protein of 32 amino acids produced in parafollicular C cells of the thyroid, regulation of Ca2+ and Pi metabolism
Calcitonin gene-related peptide (CGRP) protein of 37 amino acids, product of the calcitonin gene derived by alternative splicing of the precursor mRNA in the brain acts as a vasodilator
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Parathyroid Hormone
Parathyroid hormone (PTH) protein of 84 amino acids regulation of Ca2+ and Pi metabolism, stimulates bone resorption thus increasing serum [Ca2+], stimulates Pi secretion by kidneys
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Adipose Tissue Hormones

Adipose Tissue page (more complete listing)
Leptin 167 amino acid precursor processed to 146 amino acids regulation of overall body weight by limiting food intake and increasing energy expenditure, regulation of the neuroendocrine axis, inflammatory responses, blood pressure, and bone mass
Adiponectin 244 amino acid protein with 4 distinct functional domains major biological actions are increases in insulin sensitivity and fatty acid oxidation
Resistin 108 amino acid pre-protein in humans induces insulin resistance
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Hormones and Peptides of the Gut

additional discussion of gut hormones: Gut-Brain Interrelationships page
Cholecystokinin, CCK predominant form is 33 amino acids stimulates gallbladder contraction and bile flow, increases secretion of digestive enzymes from pancreas
Enterostatin derived from N-terminal end of pancreatic colipase; pentapeptide sequence of human enterostatin is APGPR regulates fat intake, peripheral or central administration inhibits consumption of a high-fat diet but not a low-fat diet
FGF19 216 amino acids; member of the large FGF family of growth factors produced in ileum, expression of gene activated by transcription factor FXR, FXR is activated when ileal enterocytes absorb bile acids, when released to the portal circulation FGF19 stimulates hepatic glycogen and protein synthesis while inhibiting glucose production
Gastrin 17 amino acids (little gastrin) and 34 amino acids (big gastrin) produced by stomach antrum, stimulates acid and pepsin secretion, also stimulates pancreatic secretions
Gastrin-releasing peptide (GRP); a bombesin-like peptide family member 27 amino acids stimulates release of gastrin from G cells of the stomach and CCK from small intestinal enteroendocrine I cells
Ghrelin 28 amino acids derived from preproghrelin protein; acylated on Ser3 with n-octanoic acid, non-acylated forms found in circulation also but not bioactive appetite stimulation, stimulates NPY release, regulation of energy homeostasis, glucose metabolism, gastric secretion and emptying, insulin secretion
Glucagon-like peptide 1 (GLP-1) formerly called enteroglucagon two forms: 31 amino acids, GLP-1(7-37) and 30 amino acids, GLP-1(7-36)amide potentiates glucose-dependent insulin secretion, inhibits glucagon secretion, inhibits gastric emptying
Glucose-dependent insulinotropic polypeptide (GIP) originally called gastric inhibitory polypeptide 42 amino acids inhibits secretion of gastric acid, enhances insulin secretion
Motilin 22 amino acids controls gastrointestinal muscles, stimulates release of PP, stimulates gallbladder contractions
Neuromedin B; a bombesin-like peptide family member 10 amino acids (amidated) secretion of gastrin, CCK, GIP, insulin; smooth muscle contraction; enhances food intake
Obestatin 23 amino acids derived from preproghrelin protein acts in opposition to ghrelin action on appetite
Oxyntomodulin 37 amino acids, the first 29 are identical to glucagon contains all of the amino acids of glucagon (see Figure below); inhibits meal-stimulated gastric acid secretion similar to GLP-1 and GLP-2 action; induces satiety, decreases weight gain, and increases energy consumption; has weak affinity for GLP-1 receptor as well as glucagon receptor, may mimic glucagon actions in liver and pancreas
Secretin 27 amino acids secreted from duodenum at pH values below 4.5, stimulates pancreatic acinar cells to release bicarbonate and H2O
Somatostatin 14 amino acid version inhibits release and action of numerous gut peptides, e.g. CKK, OXM, PP, gastrin, secretin, motilin, GIP; also inhibits insulin and glucagon secretion from pancreas
Substance P, a member of the tachykinin family that includes neurokinin A (NKA) and neurokinin B (NKB) 11 amino acids CNS function in pain (nociception), involved in vomit reflex, stimulates salivary secretions, induces vasodilation;
antagonists have anti-depressant properties
Vasoactive intestinal peptide (VIP) 28 amino acids produced by hypothalamus and GI tract, relaxes the GI, inhibits acid and pepsin secretion, acts as a neurotransmitter in peripheral autonomic nervous system, increases secretion of H2O and electrolytes from pancreas and gut
Pancreatic Polypeptide (polypeptide fold) Family
Pancreatic Polypeptide, PP 36 amino acids suppresses glucose-induced insulin secretion, inhibits bicarbonate and protein secretion from pancreas
Peptide Tyrosine Tyrosine, PYY 36 amino acids inhibits gastric motility by inhibiting cholinergic neurotransmission, inhibits gastric acid secretion, induces sensations of satiety
Neuropeptide Y, NPY 36 amino acids, 5 receptors termed Y receptors effects on hypothalamic function in appetite, controls feeding behavior and energy homeostasis, levels increase during starvation to induce food intake
Amphiregulin 2 peptides: 78 amino acid truncated form and 84 amino acid form with 6 additional N-terminal amino acids homology to EGF and binds to the EGF receptor (EGFR)
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Pancreatic Hormones

Amylin 37 amino acids, intrachain disulfide bonded also called islet amyloid polypeptide (IAPP), produced by β-cells of the pancreas, co-secreted with insulin; reductes the rate of gastric emptying, suppresses of food intake, and suppresses post-meal glucagon secretion
Insulin disulfide bonded dipeptide of 21 and 30 amino acids produced by β-cells of the pancreas, increases glucose uptake and utilization, increases lipogenesis, general anabolic effects
Glucagon polypeptide of 29 amino acids produced by α-cells of the pancreas, increases lipid mobilization and glycogenolysis in order to increase blood glucose levels
Pancreatic polypeptide, PP polypeptide of 36 amino acids increases glycogenolysis, regulation of gastrointestinal activity
Somatostatin 14 amino acid version inhibition of glucagon and somatotropin release
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Placental Hormones
Estrogens steroids maintenance of pregnancy
Progestins steroids mimic action of progesterone
Chorionic gonadotropin 2 proteins: α is 96 amino acids; β is 147 activity similar to LH
Chorionic somatomammotropin
also called placental lactogen
protein of 191 amino acids acts like prolactin and GH
Relaxin 2 proteins of 22 and 32 amino acids produced in ovarian corpus luteum, inhibits myometrial contractions, secretion increases durin gestation
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Gonadal Hormones
Estrogens (ovarian) steroids: estrone (E1), estradiol (E2), and estriol (E3) estradiol is most potent estrogen and it is the major hormone involved in the maturation and function of female secondary sex organs; estrone is predominant during menopause; estriol predominates in pregnancy; estrogens promote maturation of sperm in males and contribute to libido
Progestins (ovarian) steroid: progesterone implantation of ovum and maintenance of pregnancy
Androgens (testicular) steroid: testosterone and dihydrotestosterone (DHT) maturation and function of male secondary sex organs; testosterone in females participates in bone mass and muscle mass and strength, also contributes to female libido
Inhibins A and B 1 protein (α is 134 amino acids; β is 115 and 116 amino acids) inhibition of FSH secretion
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Adrenal Cortical Hormones
Glucocorticoids steroids: cortisol and corticosterone diverse effects on inflammation and protein synthesis
Mineralocorticoids steroids: aldosterone maintenance of salt balance
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Adrenal Medullary Hormones
Epinephrine (adrenalin) derived from tyrosine classic "fight-or-flight" response, increases glycogenolysis, lipid mobilization, smooth muscle contraction, cardiac function, binds to all classes of catecholamine receptors (α- and β-adrenergic)
Norepinephrine (noradrenalin) derived from tyrosine classic "fight-or-flight" response, lipid mobilization, arteriole contraction, also acts as neurotransmitter in the CNS, released from noradrenergic neurons, binds all catecholamine receptors except β2-adrenergic
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Liver Hormones
Angiotensin II polypeptide of 8 amino acids derived from angiotensinogen (present in the α2-globulin fraction of plasma) which is cleaved by the kidney enzyme renin to give the decapeptide, angiotensin I, the C-terminal 2 amino acids are then released (by action of angiotensin-converting enzyme, ACE) to yield angiotensin II responsible for essential hypertension through stimulated synthesis and release of aldosterone from adrenal cells
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Kidney Hormones
Calcitriol [1,25-(OH)2-vitamin D3] derived from 7-dehydrocholesterol responsible for maintenance of calcium and phosphorous homeostasis, increases intestinal Ca2+ uptake, regulates bone mineralization
Erythropoietin, EPO derived from 193 amino acid precursor protein highly glycosylated hormone (40% of total mass) that is also considered a growth factor; is required for erythropoiesis in the bone marrow; exerts its effects by binding the EPO receptor, EPOR
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Cardiac Hormones
Atrial natriuretic peptide (ANP) 126 amino acid precursor is cleaved to release an N-terminal peptide that is similar to vasoactive peptide, the C-terminus possesses the ANP activity released from heart atria in response to hypervolemia; actions include natriuresis, diuresis, vasorelaxation, inhibition of renin and aldosterone secretion, aalso plays a key role in cardiovascular homeostasis
Natriuretic peptide B (BNP) precursor BNP is cleaved intracellularly and then also when released to the blood released from heart ventricles in response to hypervolemia; original mammalian BNP was isolated from brain but the human brain natriuretic factor is CNP; BNP and ANP act by binding to the same receptor; actions include natriuresis, diuresis, vasorelaxation, inhibition of renin and aldosterone secretion, also plays a key role in cardiovascular homeostasis
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Pineal Hormones
Melatonin N-acetyl-5-methoxytryptamine regulation of circadian rhythms

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Michael W King, PhD | © 1996–2016, LLC | info @

Last modified: November 18, 2016