Treatment of moderate to severe hypertensive patients with an orally active converting-enzyme inhibitor.

Seventeen hypertensive patients were treated with captopril, an orally active inhibitor of converting-enzyme. All patients showed a fall in blood pressure (BP), although in some patients only after the addition of diuretics. In 2 patients a skin rash developed. One patient developed proteinuria. A renal biopsy revealed membranous glomerulopathy. Correlations were found between pretreatment plasma renin activity (PRA) and the decrease in BP, and between pretreatment PRA and the decrease in plasma aldosterone concentration (PAC). Filtration fraction (FF) fell, indicating a decrease in renal vascular resistance. Captopril decreased the sensitivity to exogenous angiotensin I (AI), dependent on the captopril dose used. The sensitivity to exogenous bradykinin increased impressively even on the lowest dose of the drug. These observations suggest extrapulmonary conversion of AI to angiotensin II (AII).