2004 Volume 95 Issue 3 Pages 394-397
We examined the combined effects of the calcium channel blockers 1,4-dihydropyridine (benidipine) and benzothiazepine (diltiazem) on vasopressin-induced myocardial ischemia in anesthetized rats, an experimental model of angina. Benidipine (3, 10 μg/kg, i.v.) and diltiazem (300, 1000 μg/kg, i.v.) caused dose-related inhibition of vasopressin-induced S-wave depression, an index of myocardial ischemia. Co-administration of low doses of benidipine (3 μg/kg) and diltiazem (300 μg/kg) almost completely inhibited the S-wave depression, where the efficacy was similar to that obtained with the use of high doses of benidipine (10 μg/kg) or diltiazem (1000 μg/kg). These results suggest that the administration strategy employed may be useful in the treatment of angina pectoris.