Calcium channel blockade with nitrendipine. Effects on sodium homeostasis, the renin-angiotensin system, and the sympathetic nervous system in humans.

Publisher Website
Google Scholar
Abstract
The antihypertensive effect of the calcium channel blocking drug nitrendipine may be in part related to natriuresis. Subjects (16, 8 normal, 8 hypertensive) were given placebo for 8 days followed by nitrendipine titrated to 20 mg twice daily for 8 days. The same diet was prepared for each meal for the entire study. Na intake was fixed for each subject and averaged 150 meq/day. All urine was collected every day. Blood was drawn at the end of the placebo and nitrendipine periods for renin, aldosterone, and norepinephrine values. Nitrendipine caused a significant increase (P < 0.05) in cumulative Na excretion of 161 meq over 7 days in the normal subjects and 103 meq in hypertensive subjects. K excretion was unaffected. In both hypertensive and normal subjects, plasma renin and plasma norepinephrine activity increased significantly (P < 0.05), while plasma aldosterone levels did not change. Upright systolic blood pressure decreased significantly (P < 0.05) in both groups, whereas upright diastolic blood pressure decreased only in hypertensive subjects. The blood pressure lowering effects of this drug may be in part related to natriuretics and that C channel blockade may dissociate plasma renin activity from that of aldosterone.