The calcium antagonist isradipine and its effect on blood pressure related to plasma renin activity.

This study was designed to test the hypothesis that peripheral vein plasma renin activity is a determinant of the magnitude of the hypotensive effect of the calcium antagonist Isradipine when given to mild to moderately severe essential hypertensives. There was significant relationship between plasma renin activity and blood pressure reduction by Isradipine. The lower the plasma renin activity the greater the blood pressure reduction. Both plasma volume and initial diastolic blood pressure level were not determinants. Thus, low peripheral vein plasma renin activity is a determinant (marker) of the hypotensive effect of Isradipine in mild to moderately severe uncomplicated essential hypertensives.