Abstract: Objective: To investigate the effects of different doses of ethanol on acute myocardial ischemia in rabbits.Methods: Thirty six rabbits were randomly divided into the control group, pituitrin group,5% ethanol+pituitrin group,10% ethanol+pituitrin group,20% ethanol+pituitrin group and 30% ethanol+pituitrin group.The hemodynamics and electrocardiogram in different groups were observed. After the end of the experiment,the activities of plasma creatine kinase(CK)and lactate dehydrogenase(LDH)were measured.Results: Compared with the cotrol group,the ST segment significantly elevated,the breadth of T wave at 1 min,3 min and 5 min significantly increased,and the activities of CK and LDH significantly increased in pituitrin group and 30% ethanol+ pituitrin group(P<0.05).Compared with pituitrin group,the ST segment and T wave breadth decreased,and the activities of CK and LDH significantly increased in 5% ethanol+ pituitrin group and 10% ethanol+pituitrin group(P<0.05). Conclusions: The 5% and 10% ethanol have protective effects on acute myocardial ischemia induced by pituitrin in rabbits, while 30% ethanol can aggravate the myocardial ischemia.