Objective: To observe the effects of tetramethylpyrazine injection on the angiogenesis and expression of vascular endothelial growth factor(VEGF)mRNA in ischemic myocardium of the rats with myocardial infarction(MI). Method :The left coronary artery of male Wistar rat was ligated to make the model of acute myocardial infarction.All rats were randomly divided into Tetramethylpyrazine injection group

Shexiang Baoxin Pills group(positive control group)

model group and sham operation group. Microvasscular vascular density(MVD) and VEGF mRNA in ischemic myocardium of rats with MI were detected six weeks later. Result :MVC and MVD in ischemic myocardium of rats with MI in modle group

tetramethylpyrazine injection group and Shexiang Baoxin Pills group were higher than that in sham operation group.In tetramethylpyrazine injection group they were the same as Shexiang Baoxin Pills group

which were higher than that in modle group.The expression of VEGFmRNA in modle group were elevated compared with that in sham operation group.It was significantly elevated in tetramethylpyrazine injection group compared with that in modle group and lower than that in Shexiang Baoxin Pills group. Conclusion :tetramethylpyrazine injection may promote angiogenesis in ischemic myocardium of the rats with MI.One of the mechanisms might be that tetramethylpyrazine injection could promot the expression of VEGFmRNA in ischemic myocardium of the rats with MI.