Objective: To explore the effect and mechanism of breviscapine against myocardial ischemia/reperfusion injury in rat. Method : 40 SD rats were randomly divided into sham operation group

ischemia/reperfusion group and breviscapine group. Rats in breviscapine group were injected with breviscapine 25

50 mg·kg1·d-1 respectively prior to ischemia/reperfusion. The other two groups were given normal saline instead of breviscapine equally in volume at a week before the operation.The myocardial ischemia/reperfusion model was established by ligating the left anterior descending branch of coronary artery. Apoptosis of myocytes was detected after operation in all groups by flow cytometry with AnnexinⅤand propidium iodiode (PI) staining. The ultrastructural alterations were observed under the transmission electron microscopy. Result: breviscapine could decrease the occurrence rate of myocardial apoptosis during ischemia/reperfusion injury obviously(P<0.05

P<0.01). The degree of injury on ultrastructures of myocardial cell in breviscapine group is rather alleviated compared with that in the ischemia/reperfusion group. Conclusion: breviscapine may protect myocardial cells during ischemia/reperfusion injury and the protective mechanism may be achieved by inhibiting myocardial apoptosis.