Effects of Aldosterone
In adrenal insufficiency - Na+ lost in urine and K+ retained.
In mineralocorticoids excess -
K+ and H+ loss with urine.
Water retention with Na+ and hypertension will develop.
After certain level – Na+ excretion increase due ANP effect –escape phenomenon.
Regulation of mineralocorticoids
Stmulated by
ACTH
Angiotensin II
Direct stimuli of rise plasma K+ concentration on adrenal cortex – conversion of cholesterol to pregnenolone and corticosterone to aldosterone.
ACTH –
Amount need is higher than need for glucocorticoid.
Effect is transient -
after 1-2 hr aldosterone level decrease.