Plasma Renin Activity in Human Hypertension

In three groups of patients with hypertension and increased plasma renin activity (PRA) therapeutic measures primarily designed to lower blood pressure were associated with a decrease in PRA.First, high values for PRA were found in 12 patients with severe hypertension. When they were treated with sympatholytic drugs or sympathectomy, marked decreases in PRA and urinary aldosterone excretion were observed.Second, in 23 women receiving oral contraceptives, who were referred for investigation of hypertension, mean PRA was greater than in a comparable group of hypertensive controls. In six patients cessation of oral contraceptives, resulted in decreases in PRA, urinary aldosterone excretion, and blood pressure.Third, in a group of 50 patients with severe uremia, PRA was greater in those with hypertension than in those without. A significant correlation existed between PRA and mean blood pressure. Bilateral nephrectomy was carried out in 14 severely hypertensive patients, including 10 in whom maintenance dialysis had failed to control blood pressure. The removal of the kidneys was shown to facilitate the control of blood pressure in 12 cases.It is suggested that hyperfunction of the renin-aldosterone system may have a role in the pathogenesis of hypertension other than that of the Goldblatt type.