THE SELECTIVE ANTIANGINAL EFFECT WITHOUT CHANGING BLOOD-PRESSURE OF BUTYLIDENEPHTHALIDE IN CONSCIOUS RATS

Synthetic butylidenephthalide (Bdph), 60 mg/kg per os (p.o.) given 3 h prior to injection of pituitrin (4 U/kg, i.v.), significantly prevent ed T-wave lowering on lead II electrocardiograph in unanesthetized rat s, The effective dose, 60 mg/kg, was about 1/56th of the median lethal dose (LD50 p.o.) in rats. However, Bdph (60 mg/kg, p.o.) did not affe ct systolic pressure and heart rate in unanesthetized rats. Therefore, Bdph, found in the rhizome of Ligusticum chuaxiong Hort. (L. wallichi i Franch., Umbelliferae), appears to have selective antianginal effect without changing blood pressure and heart rate.