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EndocrinE ` endocrine—Physiology EndocrinE ` endocrine—Physiology SEcTion iii 329

Growth hormone
Also called somatotropin. Secreted by anterior
Sleep, hypoglycemia, stress Aging, obesity, glucose pituitary.
GHRH Stimulates linear growth and muscle mass
Somatostatin
through IGF-1 (somatomedin C) secretion by
liver.  insulin resistance (diabetogenic).
Released in pulses in response to growth
hormone–releasing hormone (GHRH).
Secretion  during exercise, deep sleep, puberty,
Posterior hypoglycemia, CKD.
Anterior pituitary Secretion  by glucose, somatostatin,
pituitary somatomedin (regulatory molecule secreted
by liver in response to GH acting on target
tissues).
Growth Excess secretion of GH (eg, pituitary adenoma)
hormone
may cause acromegaly (adults) or gigantism
(children). Treatment: somatostatin analogs
(eg, octreotide) or surgery.

Amino acid uptake IGF-1 Amino acid uptake Glucose uptake
Protein synthesis Protein synthesis Lipolysis
DNA and RNA synthesis
Chondroitin sulfate
Collagen
Cell size and number

Antidiuretic hormone Also called vasopressin.

soUrce Synthesized in hypothalamus (supraoptic and
paraventricular nuclei), stored and secreted by
posterior pituitary.
FUnction Regulates b1ood pressure (V 1 -receptors) and ADH level is  in central diabetes insipidus (DI),
serum osmolality (V 2 -receptors). Primary normal or  in nephrogenic DI.
function is serum osmolality regulation (ADH Nephrogenic DI can be caused by mutation in
 serum osmolality,  urine osmolality) via V 2 -receptor.
regulation of aquaporin channel insertion in Desmopressin (ADH analog) is a treatment for
principal cells of renal collecting duct. central DI and nocturnal enuresis.
regUlAtion Plasma osmolality (1°); hypovolemia.

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