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Common Vertebrate Hormones
HormoneStructureFunctions
Pituitary Hormones
Oxytocinpolypeptide of 9 amino acids
CYIQNCPLG (C's are disulfide bonded)
uterine contraction, causes milk ejection in lactating females, responds to suckling reflex and estradiol, lowers steroid synthesis in testes
Vasopressin
(antidiuretic hormone, ADH)
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
Melanocyte-stimulating hormones (MSH)a polypeptide = 13 amino acids
b polypeptide = 18 amino acids
g polypeptide = 12 amino acids
pigmentation
Corticotropin (adrenocorticotropin, ACTH)polypeptide = 39 amino acidsstimulates cells of adrenal gland to increase steroid synthesis and secretion
Lipotropin (LPH)b polypeptide = 93 amino acids
g polypeptide = 60 amino acids
increases fatty acid release from adipocytes
Thyrotropin (thyroid-stimulating hormone, TSH)2 proteins: a is 96 amino acids; b is 112acts on thyroid follicle cells to stimulate throid hormone synthesis
Growth hormone (GH, or somatotropin)protein of 191 amino acidsgeneral anabolic stimulant, increases release of insulin-like growth factor-I (IGF-I), cell growth and bone sulfation
Prolactin (PRL)protein of 197 amino acidsstimulates differentiation of secretory cells of mammary gland and stimulates milk synthesis
Luteinizing hormone (LH); human chorionic gonadotropin (hCG) is similar and produced in placenta2 proteins: a is 96 amino acids; b is 121increases 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)2 proteins: a is 96 amino acids; b is 120ovarian follicle development and ovulation, increases estrogen production; acts on Sertoli cells of semiferous tubule to increase spermatogenesis
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Hypothalamic Hormones
Corticotropin-releasing factor (CRF or CRH)protein of 41 amino acidsacts on corticotrope to release ACTH and b-endorphin (lipotropin)
Gonadotropin-releasing factor (GnRF or GnRH) polypeptide of 10 amino acidsacts on gonadotrope to release LH and FSH
Prolactin-releasing factor (PRF)this may be TRHacts on lactotrope to release prolactin
Prolactin-release inhibiting factor (PIF)may be derived from GnRH precursor, 56 amino acidsacts on lactotrope to inhibit prolactin release
Growth hormone-releasing factor (GRF or GRH)protein of 40 and 44 amino acidsstimulates GH secretion
Somatostatin (SIF, also called growth hormone-release inhibiting factor, GIF)polypeptide of 14 and 28 amino acidsinhibits GH and TSH secretion
Thyrotropin-releasing factor (TRH or TRF)polypeptide of 3 amino acids: EHPstimulates TSH and prolactin secretion
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Thyroid Hormones
Thyroxine and triiodothyronineiodinated dityrosin derivativesresponds to TSH and stimulates oxidations in many cells
Calcitoninprotein of 32 amino acidsproduced 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 brainacts as a vasodilator
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Parathyroid Hormone
Parathyroid hormone (PTH)protein of 84 amino acidsregulation of Ca2+ and Pi metabolism, stimulates bone resorption thus increasing serum [Ca2+], stimulates Pi secretion by kidneys
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Digestive Hormones
additional Table of gastrointestinal hormones
Gastrinpolypeptide of 17 amino acidsproduced by stomach antrum, stimulates acid and pepsin secretion, also stimulates pancreatic secretions
Secretinpolypeptide of 27 amino acidssecreted from duodenum at pH values below 4.5, stimulates pancreatic acinar cells to release bicarbonate and H2O
Cholecystokinin (CCK)polypeptide of 33 amino acidsstimulates gallbladder contraction and bile flow, increases secretion of digestive enzymes from pancreas
Motilinpolypeptide of 22 amino acidscontrols gastrointestinal muscles
Vasoactive intestinal peptide (VIP)polypeptide of 28 residuesproduced 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
Gastri inhibitory peptide (GIP)polypeptide of 43 amino acidsinhibits secretion of gastrin
Somatostain14 amino acid versioninhibits gastrin secretion from stomach and glucagon secretion from pancreas
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Pancreatic Hormones
Insulindisulfide bonded dipeptide of 21 and 30 amino acidsproduced by b-cells of the pancreas, increases glucose uptake and utilization, increases lipogenesis, general anabolic effects
Glucagonpolypeptide of 29 amino acidsproduced by a-cells of the pancreas, increases lipid mobilization and glycogenolysis in order to increase blood glucose levels
Pancreatic polypeptidepolypeptide of 36 amino acidsincreases glycogenolysis, regulation of gastrointestinal activity
Somatostatin14 amino acid versioninhibition of glucagon and somatotropin release
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Placental Hormones
Estrogenssteroidsmaintenance of pregnancy
Progestinssteroidsmimic action of progesterone
Chorionic gonadotropin2 proteins: a is 96 amino acids; b is 147activity similar to LH
Placental lactogenprotein of 191 amino acidsacts like prolactin and GH
Relaxin2 proteins of 22 and 32 amino acidsproduced in ovarian corpus luteum, inhibits myometrial contractions, secretion increases durin gestation
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Gonadal Hormones
Estrogens (ovarian)steroids; estradiol and estronematuration and function of female secondary sex organs
Progestins (ovarian)steroid; progesteroneimplantation of ovum and maintenance of pregnancy
Androgens (testicular)steroid; testosteronematuration and function of male secondary sex organs
Inhibins A and B1 protein (a is 134 amino acids; b is 115 and 116 amino acidsinhibition of FSH secretion
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Adrenal Cortical Hormones
Glucocorticoidssteroids; cortisol and corticosteronediverse effects on inflammation and protein synthesis
Mineralocorticoidssteroids; aldosteronemaintenance of salt balance
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Adrenal Medullary Hormones
Epinephrine (adrenalin)derived from tyrosineglycogenolysis, lipid mobilization, smooth muscle contraction, cardiac function
Norepinephrine (noradrenalin)tyrosine derivativelipid mobilization, arteriole contraction
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Liver Hormones
Angiotensin IIpolypeptide of 8 amino acids derived from angiotensinogen (present in the a2-globin 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 IIresponsible 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-dehydrocholesterolresponsible for maintenance of calcium and phosphorous hoemostasis, 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 precursorreleased 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
MelatoninN-acetyl-5-methoxytryptamineregulation of circadian rhythms
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This article has been modified by Dr. M. Javed Abbas.
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20:50 21/12/2002