Endocrine Flashcards
What is the adrenal cortex derived from?
Mesoderm
What is the adrenal medulla derived from?
Neural crest cells
What is the zona glomerulosa regulated by and what does it produce?
AT II
Mineralocorticoids (aldosterone)
What is the zona Fasciculata regulated by and what does it produce?
ACTH, CRH
Glucocoriticoids (cortisol)
What is the zona Reticularis regulated by and what does it produce?
ACTH, CRH
Androgens (DHEA)
What are the cells of the adrenal medulla?
Chromaffin cells
What is the adrenal medulla regulated by and what does it produce?
Preganglionic SNS
Catecholamines (epi/norepi)
What are the insulin dependent transporters and in what tissues would you find them?
GLUT4: adipose tissue, striated muscle
What are the insulin independent transporters and in what tissues would you find them?
GLUT1: RBCs, brain, cornea, placenta
GLUT2 (bidirectional): β islet cells, liver, kidney, small intestine
GLUT3: brain, placenta
GLUT5 (fructose): spermatocytes, GI tract
What tonically inhibits prolactin?
Dopamine from the hypothalamus
Function of Ghrelin
Stimulates hunger (orexigenic effect) and GH release (via GH secretagog receptor) Produced by stomach
Function of Leptin
Satiety hormone. Produced by adipose tissue.
Function of endocannabinoids
Act at cannabinoid receptors in hypothalamus and nucleus accumbens, two key brain areas for the homeostatic and hedonic control of food intake: ↑ appetite
ADH
Synthesized in hypothalamus; released by post pit
Regulates serum osmolarity (V2-r)and BP (V1-r)
17 alpha hydroxylase def leads to what?
Incr: mineralocorticoids (aldosterone), BP
Decr: cortisol, sex hormones, [K]
21-hydroxylase def leads to what?
Incr: sex hormones, [K], renin
Decr: aldosterone, cortisol, BP
Mechanism of Ca homeostasis
↑ in pH -> ↑ in affinity of albumin for Ca -> hypocalcemia
Function of vitamin D
↑ absorption of dietary Ca2+ and PO43−
Enhances bone mineralization
Function of PTH
↑ bone resorption of Ca2+ and PO43−
↑ kidney reabsorption of Ca2+ in DCT
↓ reabsorption of PO43− in PCT
↑ calcitriol production by stimulating kidney 1α hydroxylase in proximal convoluted tubule
Source of PTH
Chief cells of parathyroid
Source of calcitonin
Parafollicular cells (C cells) of thyroid
Function of calcitonin
↓ bone respiration of Ca (tones done serum Ca)
Endocrine hormones that signal via cAMP
FSH, LH, ACTH, TSH, CRH, hCG, ADH (V2-receptor), MSH, PTH, calcitonin, GHRH, glucagon, histamine (H2-receptor)
(FLAT ChAMP)