Abstract: Abstract: Objective　To study the protective effect of epicatechin (EC) on cerebral ischemia-reperfusion in rats and its influence on antioxidant capacity. Methods　Ninety male SD rats were divided into 6 groups according to the random number table method, with 15 rats in each group, namely the sham operation group (Sham group), the model group (I/R group), EC 5 mg/kg group, EC 10 mg/kg group, EC 20 mg/kg group and edaravone 3 mg/kg group (ED 3 mg/kg group). Except for the Sham group, the other groups were established the middle cerebral artery embolism (MCAO) model by the thread embolization method. After the ischemia for 2 h, the drug was administered at the time points of 0 h, 12 h and 24 h after reperfusion. The Longa neurological function score was performed at the 12th and 24th hour. Triphenyltetrazolium chloride (TTC) was used to detect the infarct area of the ischemic side of the brain at the 36 h. Hematoxylin eosin (H&E) staining was used to observe the morphological changes of the ischemic side of the brain. Colorimetric method was used to detect the content of malondialdehyde (MDA), the activity of superoxide dismutase (SOD) and the activity of glutathione peroxidase (GPx) in the serum and the brain tissue of ischemic side of the brain. Results　Compared with the Sham group, the neurological function score and the percentage of infarct area were increased in the I/R group (P＜0.05). The tissue morphology was significantly changed, the serum and brain tissue contents of MDA were increased, while the activity of SOD was decreased (P＜0.05). The activity of GPx was decreased in brain tissues (P＜0.05). Compared with the I/R group, the neurological function scores and the percentage of infarct area were decreased in the EC 10 mg/kg group, EC 20 mg/kg group and ED 3 mg/kg group (P＜0.05). The tissue damage was improved. The content of MDA in serum and brain tissue decreased, while the activity of SOD increased (P＜0.05). The activities of GPx in brain tissues increased in EC 10 and 20 mg/kg group and ED 3 mg/kg group (P＜0.05). Conclusion　Epicatechin can resist cerebral ischemia-reperfusion injury by enhancing brain antioxidant capacity in rats, which is dose-dependent within a certain range.

Key words: catechin, brain ischemia, reperfusion injury, malondialdehyde, superoxide dismutase, glutathione peroxidase, antioxidants, epicatechin