The biosynthesis of adrenal steroids: effects of angiotensin II, adrenocorticotropin, and potassium.

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Abstract
The effects of angiotensin, ACTH, and K alone and in various combinations upon the synthesis of aldosterone, corticosterone, and cortisol by slices of beef adrenal tissue have been studied. In relatively small doses, angiotensin usually stimulated the synthesis of aldosterone to a much greater degree than that of cortisol, whereas ACTH stimulated the synthesis of cortisol without an effect upon aldosterone. Increasing concentrations of K stimulated the synthesis of aldosterone and corticosterone but not of cortisol. The effect of angiotensin was potentiated by amounts of ACTH and K that did not themselves influence steroid synthesis. The possible mechanism by which angiotensin stimulates steroid synthesis was also investigated. Angiotensin did not affect adrenal phosphorylase activity and was potentiated by adenosine-3 '', 5 ''-monophosphate, suggesting that it does not act via a mechanism proposed for the action of ACTH. Evidence is presented for a site of action of angiotensin relatively early in the biosynthetic pathway before the conversion of corti -costerone to aldosterone.