Diurnal variation of plasma renin activity, aldosterone and cortisol in idiopathic edema.

Abstract

The plasma levels of aldosterone (PA), renin activity (PRA) and cortisol were measured every 30 min in the supine position in 4 women with idiopathic edema. The circadian rhythm of PA was similar to that previously reported in normal subjects: peak secretory episodes occurred during the latter part of sleep and shortly after awakening. Moreover the levels of PA were statistically significantly correlated with PRA and cortisol in 3 of the 4 patients (P < .005). Secretory spikes followed meals by 30 min and furosemide administration by 4 h. It is concluded that, 1) as in normals, a central nervous system rhythm may be important in control of PA, and 2) potassium is suggested as the secretagogue of aldosterone after meals. Comparison of the circadian hormone levels in the patients with those previously found in normals revealed only one subject who had significantly lower PRA than normals, and one patient with a higher PA during the midnight to 0800 h period than controls. The other levels were not significa...