Relationship of plasma renin activity and aldosterone levels with hemodynamic functions in essential hypertension.

Correlates of plasma renin activity and plasma aldosterone levels with hemodynamic functions were studied in 47 male patients with untreated, permanent essential hypertension. All subjects had a normal creatinine clearance and received a diet of 110 mEq/day of sodium. Supine plasma renin activity was directly correlated with cardiac index (P less than.01) and cardiopulmonary blood volume (P=.01). Percentage changes in plasma renin activity and total peripheral resistance in response to upright position were positively correlated (P less than.001). Supine plasma aldosterone level was directly correlated with stroke index (P less than .001) and negatively correlated with hear rate (P less than .05). No significant correlation of aldosterone level was observed with the other measurements, including plasma renin activity. The study points to the neural sympathetic control of plasma renin activity in essential hypertension and suggests the existence of some interrelationships between aldosterone level and cardiac performance.