Effect of dehydration on plasma renin activity

Abstract

To elucidate the effect of plasma volume on renin secretion, plasma renin activity was measured in 10 normal and hypertensive subjects during water test of VOLHARD. Water deprivation resulted in a significant increase in plasma renin activity, plasma sodium concentration and hematocrit in them except 2 patients with primary aldosteronism. Estimation of the renin activity was further carried out in S patients with diabetes insipidus. In all of them an increase in plasma renin activity as well as plasma sodium concentration was found after vasopressin injection and clinical states toward normal. These findings do not support a concept that renin secretion is dependent on a reduction in plasma sodium concentration. From the present study, it may be concluded that a dominant stimulator of renin release is a change in plasma volume rather than in plasma sodium concentration. © 1967, The Japanese Circulation Society. All rights reserved.