MCAT Hormones

Releasing and Inhibiting Factors

HYPOTHALAMUS -> ANTERIOR PITUITARY: modifies activities

Growth Hormone (GH)

ANTERIOR PITUITARY: increases bone and muscle growth, increases cell turnover rate

Prolactin

ANTERIOR PITUITARY -> MAMMARY GLAND: milk production

Thyroid-stimulating hormone (TSH)

ANTERIOR PITUITARY -> THYROID: increases synthesis and release of thyroid hormone (tropic)

Adrenocorticotropic hormone (ACTH)

ANTERIOR PITUITARY -> ADRENAL GLAND: increases growth and secretory activity of adrenal cortex

Luteinizing hormone

ANTERIOR PITUITARY -> OVARY/ TESTES: ovulation or testosterone synthesis

Follicle-stimulating hormone (FSH)

ANTERIOR PITUITARY -> OVARY / TESTES: follicle development or spermatogenesis

Antidiuretic hormone (ADH, vasopressin)

POSTERIOR PITUITARY -> KIDNEY: water retention

Oxytocin

POSTERIOR PITUITARY -> BREAST & UTERUS: milk letdown and uteral contractions

Thyroid hormone (TH, thyroxine)

THYROID: in the child it is necessary for physical and mental development; in the adult, it increases metabolic rate and temperature

Calcitonin

THYROID C CELLS -> BONE, KIDNEY, SMALL INTESTINE: lowers serum [Ca2+]

Parathyroid hormone (PTH)

PARATHYROIDS -> BONE, KIDNEY, SMALL INTESTINE: raises serum [Ca2+]

Thymosin

THYMUS: is involved in T-cell development during childhood.

Epinephrine

ADRENAL MEDULLA: sympathetic stress response (rapid)

Cortisol (glucocorticoid)

ADRENAL CORTEX: results in a longer-term stress response; increased blood [glucose]; increased protein catabolism; decreased inflammation and immunity; many other

Aldosterone (mineralocorticoid)

ADRENAL MEDULLA -> KIDNEY: increased Na+ reabsorption to increase blood pressure

Sex steroids

ADRENAL CORTEX: not normally important, but an adrenal tumor can overproduce these, causing masculinization or feminization.

Insulin

BETA CELLS OF THE ISLETS OF LANGERHANS IN THE PANCREAS: decreases blood [glucose]; increases glycogen and fat storage; it is activated at high blood [glucose] and is absent or ineffective in diabetes melitus

Glucagon

ALPHA CELLS OF THE ISLETS OF LANGERHANS IN THE PANCREAS: secreted at low blood [glucose] and results in an increase in blood [glucose] and decrease in glycogen and fat storage

Somatostatin (SS)

SIGMA CELLS OF THE ISLETS OF LANGERHANS IN THE PANCREAS: inhibits many digestive processes

Testosterone

TESTES: male characteristics; spermatogenesis

Estrogen

OVARIES / PLACENTA: Female characteristics, endometrial growth

Progesterone

OVARIES / PLACENTA: leads to endometrial secretion, pregnancy

Atrial natriuretic factor (ANF)

HEART -> KIDNEY: increases urination to decrease blood pressure

Erythropoeitin

KIDNEY -> BONE MARROW: increases RBC synthesis

Regulation of [Ca2+]

Parathyroid hormone and Calcitonin

Regulation of blood [glucose]

Insulin and Glucagon

Milk production and letdown

Oxytocin and Prolactin

Secreted by the Pancreas

Glucagon (alpha) & Insulin (beta) & Somatostatin (sigma)

Involved in Pregnancy Prepping

Oxytocin, Prolactin, Progesterone, Estrogen, LH, FSH

Regulation of B.P.

Atrial natriuretic factor (ANF) & Aldosterone

Hormones that increase blood [glucose]

Glucagon (polypeptide derivative), Epinepherine (amino acid derivative), Cortisol (steroid / glucocorticoid)