ABSTRACT
Objective To improve the methods of making myocardial ischemia-reperfusion model and observe the changes of electrocardiogram and ultrastructure of myocardium in rats.Methods The chest of young male SD rats through the fourth intercostal space was opened,and the left coronary artery was tied with a silicagel tube,after 30 minutes,untied to perfuse.Changes of electrocardiogram were observed and recorded.After reperfusion,the levels of AST,LDH,and CK-MB were measured and the tissue samples of the infarct areas were examined by transmission electronic microscope.Results The 90 percent of total rats were made myocardial ischemia reperfusion model successfully.In myocardial ischemia reperfusion rats:the QRS wave of myocardial ischemia-reperfusion rats was much higher than that of control group;the level of cardiac enzymes increased;myocardial and vascular endothelial cells ultrastructure was damaged seriously.Conclusions The improvement of modus operandi is right.Ischemia reperfusion can cause evident damage of myocardial and vascular endothelial cells ultrastructure in rats,and damage of myocardial cells is more severe than vascular endothelial cells.