Effect of verapamil on renin-angiotensin-aldosterone system, urinary 6-keto prostaglandin F1 alpha and aldosterone response to metoclopramide in normal man.

Seven healthy male volunteers were studied at the end of 7 days placebo period and after 7 days treatment with verapamil (120 mg twice daily). Verapamil increased significantly plasma renin activity and urinary excretion of 6-keto prostaglandin F1 alpha without significant modification of plasma aldosterone. Metoclopramide (10 mg i. v.) induced a significant increase of plasma aldosterone with the peak values 15 min after the injection of the drug. The results indicate that verapamil does not lead to secondary hyperaldosteronism which is characteristic of most other vasodilators. The increase of prostacyclin, measured as 6-keto prostaglandin F1 alpha can contribute to the efficacy of verapamil in patients with ischemic heart disease and hypertension. The present study suggests that the aldosterone response to metoclopramide is not directly dependent on calcium, but an indirect effect of calcium through renin-angiotensin system cannot be excluded.