ABSTRACT
Objective: To observe the effects of procyanidins on myocardial apoptosis and related protein expressions of caspase-3, Bcl-2 and Bax in experimental rats with ischemia reperfusion (I/R) injury and to explore the possible mechanism. Methods: A total of 40 male SD rats were randomly assigned to 4 groups: Sham group, IR group, Low-dose procyanidin (50 mg?kg-1) group, and High-dose procyanidin (100 mg?kg-1) group. n=10 in each group and the rats were pre-treated by intra gastric drug administration once/day for 2 weeks, then left anterior descending artery (LAD) occlusion was conducted for 30 minutes followed by reperfusion for 120 minutes to establish IR model. Blood levels of CK-MB activity and myocardial infarction (MI) size were examined; protein expressions of caspase-3, Bcl-2 and Bax were determined by Western blot analysis; myocardial apoptotic index was measured by TUNEL method. Results: Compared with Sham group, IR group presented the higher CK-MB activity, enlarged MI size, increased index of apoptosis, elevated protein expressions of caspase-3 and Bax, while reduced protein expression of Bcl-2 and the ratio of Bcl-2/Bax, P<0.05. Compared with IR group, both Low-dose and High-dose procyanidin groups had the lower CK-MB activity, smaller MI size, decreased index of apoptosis, reduced protein expressions of caspase-3 and Bax, while elevated protein expression of Bcl-2 and the ratio of Bcl-2/Bax,P<0.05. Conclusion: Procyanidin could reduce myocardial apoptosis index in experimental IR rats, which might be related to decreased protein expressions of caspase-3 and Bax, increased protein expression of Bcl-2 and the ratio of Bcl-2/Bax.