Effect of tetrandrine on acute experimental myocardial infarction.

In 19 anesthetized open-chest dogs the effects of tetrandrine on experimental myocardial infarction were investigated by epicardial mapping and creatine phosphate kinase (CPK) enzyme estimation. In epicardial mapping the ΣST and NST in dogs pretreated with tetrandrine were significantly lower than the control group after 15–30 minutes following ligation of the left anterior descending artery (LAD). The difference of ΣST, NST in both groups reached peak value at 2 hours. If taking the ΣST and NST 2 minutes after ligation as 100%), ΣST in the treated dogs 2 hours after ligation would be 43% vs 91% in the control group, NST in the treated dogs 53% vs 90% in the control group. 24 hours after ligation of LAD the CPK of preserved myocardium of infarcted area in the treated dogs was more than in the control group. The CPK released to blood was obviously less in treated group. These suggested that tetrandrine had some protective effects on experimental myocardial infarction. But because the number of dogs studied was small and the effect on clinical myocardial infarction might be different from experimental model, these observations warrant further investigation.