Endocrine Hormones

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Hormones are non-nutrient chemicals which act as intercellular messengers and are produced in trace amounts. Hormones help to control growth and development, maintain metabolism and energy balance etc. Below is the list of hormones, their principal actions in the body, and their respective secretory glands/ tissue.

Gland / Tissue Hormone Chemical Nature Principal Actions
Hypothalamus Growth hormone–releasing hormone (GHRH); or Somatocrinin Peptide Causes release of growth hormone
Growth hormone inhibitory hormone (GHIH);or Somatostatin Peptide Inhibits release of growth hormone
Gonadotropin-releasing hormone (GnRH) Causes release of LH and FSH
Thyrotropin-releasing hormone (TRH) Peptide Stimulates secretion of TSH and prolactin
Corticotropin-releasing hormone (CRH) Peptide Causes release of ACTH
Prolactin-inhibiting factor (PIF) or Dopamine Amine Inhibits release of prolactin
Anterior Pituitary Human growth hormone (hGH); or Somatotropin Peptide Stimulates protein synthesis and overall growth of cells and tissues
Follicle-stimulating hormone (FSH) Peptide Causes growth of follicles in the ovaries and sperm maturation in Sertoli cells of testes
Luteinizing hormone (LH) Peptide Stimulates testosterone synthesis in Leydig cells of testes; induces ovulation, formation of corpus luteum, and estrogen and progesterone synthesis in ovaries
Thyroid-stimulating hormone (TSH); or thyrotropin Peptide Stimulates synthesis and secretion of thyroid hormones (thyroxine and triiodothyronine)
Adrenocorticotropic hormone (ACTH); or corticotropin Peptide Synthesis and secretion of steroid hormones from the adrenal cortex (cortisol, androgens, and aldosterone)
Prolactin (PRL) Peptide Promotes development of the female breasts and secretion of milk
Melanocyte-stimulating hormone (MSH) Acts on the melanocytes (melanin containing cells) and regulates pigmentation of the skin
Posterior Pituitary Anti-diuretic hormone (ADH) ; or vasopressin Peptide Increases water reabsorption by the kidneys and causes vasoconstriction and increases blood pressure
Oxytocin Peptide Stimulates milk ejection from breasts and uterine contractions at the time of child birth
Pineal Gland Melatonin Amine Help in the regulation of a 24-hour (diurnal) rhythm of our body; sleep-wake cycle, body temperature, metabolism, defense
Thyroid Tetraiodothyronine or thyroxine (T4) and triiodothyronine (T3) Amine Increases the rates of chemical reactions in most cells, thus increasing body metabolic rate
Calcitonin or thyrocalcitonin(TCT) Peptide Promotes deposition of calcium in the bones and decreases extracellular fluid calcium ion
Parathyroid Parathyroid hormone (PTH); hypercalcemic hormone Peptide Controls blood calcium ion concentration by increasing calcium absorption by the gut and kidneys and releasing calcium from bones; increases blood Ca2+ levels
Thymus Thymosins Peptide Help in differentiation of T-lymphocytes; promote production of antibodies to provide humoral immunity
Adrenal Cortex Cortisol (Glucocorticoid) Steroid Has multiple metabolic functions for controlling metabolism of proteins, carbohydrates, and fats;
also has anti-inflammatory effects; stimulate
gluconeogenesis and lipolysis
Aldosterone (Mineralocorticoid) Steroid Increases renal sodium reabsorption, potassium
secretion, and hydrogen ion secretion
Androgens (dehydroepiandrosterone, or DHEA) Steroid Play a role in the growth of axial hair, pubic hair and facial hair during puberty
Adrenal Medulla Noradrenaline or norepinephrine, adrenaline or epinephrine; commonly called as catecholamines; emergency hormones or hormones of Fight or Flight Amine Enhance effects of sympathetic division of autonomic nervous system during stress
Pancreas Insulin (β cells) Peptide Lowers blood glucose level by accelerating transport of glucose into cells, converting glucose into glycogen (glycogenesis), and decreasing glycogenolysis and gluconeogenesis; increases lipogenesis and stimulates protein synthesis
Glucagon (α cells); hyperglycemic hormone Peptide Raises blood glucose level by accelerating breakdown of glycogen into glucose in liver (glycogenolysis), converting other nutrients into glucose in liver (gluconeogenesis), and
releasing glucose into blood
Somatostatin (δ cells) Inhibits secretion of insulin and glucagon; slows absorption of nutrients from gastrointestinal tract
Testes Testosterone (Androgen) Steroid Development of male reproductive system and male secondary sexual characteristics
Inhibin Inhibits secretion of FSH from anterior pituitary
Ovaries Estrogens Steroid Promotes growth and development of female reproductive system, female breasts, and female
secondary sexual characteristics
Progesterone Steroid Supports pregnancy, prepare mammary glands
for lactation
Inhibin Inhibits secretion of FSH from anterior pituitary.
Relaxin (RLX) Increases flexibility of pubic symphysis during pregnancy; helps dilate uterine cervix during labor and delivery
Heart (not a endocrine gland) Atrial natriuretic factor (ANF) Peptide Decreases blood pressure
Kidney (not a endocrine gland) Erythropoietin Peptide Stimulates erythropoiesis (formation of RBC)
Endocrine cells of Gastro-intestinal tract Gastrin Peptide Stimulates the secretion of hydrochloric
acid and pepsinogen
Gastric Inhibitory Peptide (GIP) Peptide Inhibits gastric secretion and motility
Secretin Peptide Stimulates pancreatic acinar cells to release bicarbonate and water
Cholecystokinin (CCK). Peptide Stimulates secretion of pancreatic juice;
regulates release of bile from gallbladder;
causes feeling of fullness after eating
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