Effects of nitrendipine and cilazapril on renal hemodynamics and albuminuria in hypertensive patients with chronic renal failure.

In 11 hypertensive patients with chronic renal failure we studied the short-term effects of the calcium antagonist nitrendipine, the angiotensin-converting enzyme inhibitor cilazapril, and the combination of both drugs on blood pressure, renal hemodynamics, and proteinuria in a randomized, double-blind, placebo-controlled way. After one week of treatment, blood pressure at 2-5 h after drug administration amounted to 159 +/- 5/101 +/- 3 mm Hg (means +/- SEM) during placebo. Nitrendipine, cilazapril, and the combination lowered mean arterial pressure by 1.4 +/- 1.6 (NS), 6.0 +/- 1.7 (p less than 0.10), and 10.3 +/- 2.1% (p less than 0.01), respectively. Glomerular filtration rate did not change. As compared to placebo, renal blood flow increased and renal vascular resistance decreased significantly during the combination. Filtration fraction amounted to 22.7 +/- 1.2% during placebo and was 22.0 +/- 1.4 (NS), 20.4 +/- 1.2 (p less than 0.01), and 20.5 +/- 1.4% (p less than 0.05) during nitrendipine, cilazapril, and the combination, respectively. During nitrendipine, albuminuria was slightly higher than during placebo: 0.86 +/- 0.39 vs. 0.58 +/- 0.25 mg/min (NS). During cilazapril alone and during the combination of both drugs, albuminuria was lower as compared to nitrendipine: 0.38 +/- 0.14 mg/min (p less than 0.01) and 0.44 +/- 0.18 mg/min (p less than 0.01), respectively. The data suggest that the combination of nitrendipine and cilazapril is an effective treatment in renal hypertension. In addition, cilazapril alone as well as the combination with nitrendipine reduced albuminuria, possibly by decreasing filtration fraction and/or reduction of blood pressure.