0.1mv. The forty animals were randomly divided into five groups of eight animals each: in group I normal saline 5.2ml?kg-1?h-1 was infused (control); while in group II , III , IV and V propofol was infused at a rate of 30,45, 60,75mg?kg-1?h-1 for 30 min. MAP, HR, left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), ? dp/dtmax and myocardial oxygen consumption index were recorded before and 30 min after drug administration. Blood samples was taken at the end of 30 min propofol infusion for determination of plasma propofol concentration. Myocardial tissue was taken for electron microscopic examination in some rats. The extent of infarct area was determined by TTC staining. Results The plasma propofol concentration ranged from 3.4?0.9 to (12.9 ? 2.4) ?g/ml. Propofol significantly decreased MAP, HR, LVSP,? dp/dtmax and myocardial oxygen consumption index in a dose-dependent manner. The size of myocardial infarct area ranged from 23.7% to 29.2% but there was significant difference in the size of infarct area and myocardial ultrastructure between the five groups. Conclusions Propofol inhibits hemodynamics in rats with acute myocardial infarction but has little effect on infarct size and ultrastruture of myocardial tissue.