表儿茶素对大鼠脑缺血再灌注损伤的保护作用及抗氧化能力的影响#br#

摘要：目的　研究表儿茶素（EC）对大鼠脑缺血再灌注后的保护作用及抗氧化能力的影响。方法　取90只雄性清洁级SD大鼠，按随机数字表法分为6组，每组15只，分别为假手术组（Sham组）、CIRI模型组（I/R组）、EC 5 mg/kg组、EC 10 mg/kg组、EC 20 mg/kg组、依达拉奉（ED）3 mg/kg组。除Sham组外，其余组采用线栓法构建大脑中动脉栓塞（MCAO）模型，缺血2 h，于再灌注后0、12、24 h给药，12、24 h进行Longa法神经功能损伤评分，36 h取脑行氯化三苯基四氮唑（TTC）染色检测缺血侧脑组织梗死面积，HE染色观察缺血侧脑组织形态学变化，比色法检测血清和缺血侧脑组织中的丙二醛（MDA）含量、超氧化物歧化酶（SOD）活力以及脑组织中谷胱甘肽过氧化物酶（GPx）的活力。结果　与Sham组比较，I/R组神经功能损伤评分升高，梗死面积百分比增大（P＜0.05），组织形态明显改变，血清和脑组织中MDA含量增多、SOD活力降低（P＜0.05），脑组织中GPx活力降低（P＜0.05）。与I/R组比较，EC 10 mg/kg、EC 20 mg/kg、ED 3 mg/kg组神经功能损伤评分降低，梗死面积百分比减少（P＜0.05），组织损伤有所改善，血清和缺血侧脑组织中MDA含量减少、SOD活力升高，EC 10 mg/kg、EC 20 mg/kg、ED 3 mg/kg组脑组织中GPx活力升高（P＜0.05）。结论　EC能提高脑抗氧化能力，对抗大鼠脑缺血再灌注损伤，且在一定范围内呈剂量依赖性。

The protective effect and antioxidant capacity of epicatechin on cerebralischemia-reperfusion injury in rats#br#

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 tissuedecreased, 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.