Effects of aldosterone on blood pressure and glucose-6-phosphate dehydrogenase activity of heart muscle

Abstract

A study was made of the effects of aldosterone on the activity of heart muscle glucose-6-phosphate dehydrogenase (G6PDH) in relation to the pathogenesis of experimental hypertension. In a 17-day experiment, with rats given daily 1-μg doses of aldosterone/100 g body weight, no change in systolic pressure occurred and the specific activity (s.a.) of heart muscle G6PDH declined. Rats receiving daily 100 μg of aldosterone, or 500 μg of desoxycorticosterone acetate (DOCA) per 100 g body weight, showed a significant elevation of systolic pressure by the 17th day. This effect was accompanied by increases in the s.a. of heart muscle G6PDH, apparently preceding the development of hypertension. Evidence for a homeostatic role for aldosterone was revealed by the ability of low doses to prevent a decline in s.a. of cardiac G6PDH during fasting, and to reverse the increase produced by DOCA.