Response of plasma acth and adrenocortical hormones to potassium loading in essential hypertension

Abstract

The effect of potassium loading on plasma adrenocortical hormones concentrations in 9 patients with essential hypertension (EH) was investigated. The plasma renin activity (PRA), plasma concentrations of growth hormone (GH), ACTH, Cortisol, deoxycorticosterone (DOC), 18-hydroxy-deoxycorticoster-one (18-OH-DOC) and aldosterone, and serum electrolytes were measured before and after potassium chloride (KC1) infusion (0.33 mEq/kg/h, for one hour). The KC1 infusion caused significant increases in serum potassium levels and plasma levels of GH, ACTH, Cortisol, DOC, 18-OH-DOC and aldosterone, while PRA remained unchanged. Regression analysis at 30 min revealed significant positive correlations between ΔACTH and Δcortisol, between ΔACTH and ΔDOC, between ΔACTH and Δ18-OH-DOC. However, the relationship between ΔACTH and Δaldosterone was not statistically significant. These results suggest that (1) acute potassium loading causes a significant increase in the plasma ACTH level and increased levels of adrenocortical hormones may be produced by increased ACTH secretion, and (2) it may be considered that a part of the increased level of plasma aldosterone following acute potassium loading may arise from increased ACTH secretion in EH. © 1982, The Japanese Circulation Society. All rights reserved.