Common Vertebrate Hormones

Hormone	Structure	Functions
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
Vasopressin (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 control of appetite and feeding behaviors via melanocortin receptor (MC4R)-expressing neurons in hypothalamuss, 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 (GRF or GRH)	protein of 40 and 44 amino acids	stimulates GH secretion
Somatostatin (SIF, also called growth hormone-release inhibiting factor, GIF)	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 dityrosin 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 P_i 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 P_i metabolism, stimulates bone resorption thus increasing serum [Ca²⁺], stimulates P_i secretion by kidneys
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Adipose Tissue Hormones
Adipose Tissue page
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
Bombesin, also called neuromedin B and gastrin-releasing peptide	14 amino acids	stimulates release of gastrin and CCK
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	polypeptide of 42 amino acids	inhibits secretion of gastric acid, enhances insulin secretion
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
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
Obestatin	23 amino acids derived from preproghrelin protein	acts in opposition to ghrelin action on appetite
Gastrin	17 amino acids	produced by stomach antrum, stimulates acid and pepsin secretion, also stimulates pancreatic secretions
Secretin	27 amino acids	secreted from duodenum at pH values below 4.5, stimulates pancreatic acinar cells to release bicarbonate and H₂O
Cholecystokinin, CCK	predominant form is 33 amino acids	stimulates gallbladder contraction and bile flow, increases secretion of digestive enzymes from pancreas
Motilin	22 amino acids	controls gastrointestinal muscles, stimulates release of PP, stimulates gallbladder contractions
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
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
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: estradiol and estrone	maturation and function of female secondary sex organs
Progestins (ovarian)	steroid: progesterone	implantation of ovum and maintenance of pregnancy
Androgens (testicular)	steroid: testosterone	maturation and function of male secondary sex organs
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
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Cardiac Hormones
Atrial natriuretic peptide (ANP)	several active peptides cleaved from a 126 amino acid precursor	released from heart atria in response to hypovolemia, acts on outer adrenal cells to decrease aldosterone production; smooth muscle relaxation
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Pineal Hormones
Melatonin	N-acetyl-5-methoxytryptamine	regulation of circadian rhythms

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Last modified: March 10, 2012

Return to The Medical Biochemistry Page

Common Vertebrate Hormones

Last modified: March 10, 2012

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