Effect of Plasma [K+] on the Secretion of Aldosterone

TLDR

The study varied adrenal arterial potassium by intra‑arterial infusion of K⁺‑enriched solutions into an autotransplanted adrenal gland in conscious sheep and measured aldosterone, corticosterone, and cortisol secretion before and during infusion. Elevating adrenal arterial potassium increased aldosterone secretion in both sodium‑replete and sodium‑depleted sheep, with a dose‑dependent response up to ~1 mEq/L and little additional effect beyond that, and the responsiveness pattern was similar in both groups. Endocrinology 85:381, 1969.

Abstract

Levels of adrenal arterial [K+] were varied by close intra-arterial infusion of [K+] enriched solutions to the single autotransplanted adrenal gland of the conscious sheep. Secretion rates of aldosterone, corticosterone and cortisol were determined before and during infusion of KC1 solutions. In both Na replete and Na depleted sheep, elevation of adrenal arterial [K+] was associated with increased aldosterone secretion, even with small (0.5 mEq/1 or less) changes in plasma [K+]. Larger elevations of plasma [K+]—up to about 1 mEq/1—produced correspondingly larger elevations in aldosterone secretion; increases beyond 1 mEq/1 produced little further effect. A similar order of responsiveness to similar elevations of plasma [K+] was seen in Na replete and Na depleted sheep. (Endocrinology85: 381, 1969)