Nisoldipine (BAY K 5552), a new calcium antagonist. Antihypertensive effect in conscious, unrestrained renal hypertensive dogs

Abstract

The antihypertensive effect of nisoldipine (BAY K 5552), a new calcium antagonist with peripheral vasodilator properties, was studied by a radio-telemetric method in conscious, unrestrained renal hypertensive dogs. Nisoldipine has a long lasting antihypertensive action (12 hr at 0.3 mg/kg p.o.) in comparison with nifedipine (6 hr at 3.15 mg/kg p.o.). Its antihypertensive efficacy is equal to that of minoxidil and superior to nifedipine, hydralazine, diltiazem and verapamil. After nisoldipine, only a short lasting initial reflex tachycardia was noted, whereas after the other vasodilators tachycardia persisted for the entire period of blood pressure reduction. Diltiazem and verapamil produced almost no tachycardia. In some cases a bradycardia was observed after high doses of verapamil.