ANTIANGINAL EFFECTS OF YM430, A NOVEL CALCIUM ENTRY-BLOCKING AND BETA-ADRENOCEPTOR-BLOCKING AGENT IN SEVERAL EXPERIMENTAL ANGINA MODELS

1. We evaluated the antianginal effects of YM430 in several experiment al models in vitro and in vivo. 2. In isolated dog coronary artery, YM 430 (10(-8)-10(-6) M) inhibited 3,4-diaminopyridine-induced rhythmic c ontractions with an IC50 value of 59.2 nM. 3. In anesthetized rats, YM 430 (10-100 mg/kg PO) inhibited arginine vasopressin-induced ST-segmen t depression with an IC50 value of 36.6 mg/kg PO. 4. In anesthetized d ogs, YM430 (0.3 mg/kg IV) significantly inhibited ST-segment elevation induced by coronary artery occlusion. 5. These findings suggest that YM430 may be of value in the treatment of various types of angina pect oris such as variant and stable angina. (C) 1997 Elsevier Science Inc.