Objective: To explore the pathomorphological changes of myocardial of rats with acute myocardial infarction and the interfering effects of Xuemaitong capsule(XMT). Method: The Wistar rats were randomized into 5 groups

the model group

the sham operation group

the three difference dose groups of XMT preconditioning. The model rats were treated by continuous 14 days intragastric administration. After 14 days

except the sham operation

myocardial infarction of the other groups were established by ligation of coronary artery.Before and after ligation

electrocardiogram were recorded in 5

30

60

90

120 minutes

24 hours;pathomorphological change were checked by HE staining. Result: Compared with the high dose

in middle dose and low dose group

the J point were decreased. Pathological alteration of myocardial infarction showed that myocardial endometrial focal disordered arrangement

muscle cells swelling or necrosis

adventitia focal necrosis

and infiltration of inflammatory cells. Compared high and middle groups to model group

the pathomorphological change were slightly among high and middle groups. By semi-quantitative

the pathomorphological changes proved to be true (P<0.05). Conclusion: XMT has important protective function for acute myocardial infarction.