Secretion of aldosterone by rats

Abstract

The effect of sodium deprivation on adrenal blood flow and secretion of aldosterone and corticosterone was measured in intact rats. The changes induced by sodium deprivation were then compared with those resulting from infusion of angiotensin and vasopressin into hypophysectomized-nephrectomized animals and with the effect of angiotensin in oil given chronically to hypophysectomized rats. Sodium deprivation caused increased secretion of aldosterone but decreased secretion of corticosterone. Small doses of angiotensin infused acutely increased secretion of corticosterone but had no effect on aldosterone secretion. Large doses of either polypeptide increased both corticosterone and aldosterone. Chronic administration of small doses of angiotensin in oil increased corticosterone secretion but had no effect on secretion of aldosterone. Because angiotensin and vasopressin increase while sodium deprivation decreases secretion of corticosterone, it is concluded that neither of these polypeptides is responsible for the stimulation of aldosterone secretion which occurs with sodium deprivation.