中文摘要：

目的：观察罗布麻叶提取物（apocynum venetum leaf extract AVLE）预处理对心肌缺血再灌注（MI/R）损伤的影响。方法：采用SD大鼠MI/R模型,随机分为sham（假手术）组、MI/R组、AVLE预处理＋MI/R组,检测血流动力学,采用氯化三苯基四氮唑和伊文思蓝双染法检测心梗面积、以血浆肌酸激酶（CK）和乳酸脱氢酶（LDH）活性检测心肌损伤情况、以超氧化物、丙二醛（MAD）和超氧化物歧化酶（SOD）含量检测心肌氧化应激以及Western blot方法检测gp91phox的表达。结果：与MI/R组相比,AVLE预处理组左室压上升、下降最大速率（±LVdp/dtmax）升高（P〈0.05）,心肌梗死面积减少,两组分别为41.5±4.5%和32.0±3.5%（P〈0.05）,血浆CK和LDH活性分别降低到1653±62 U/L和2461±152 U/L（P〈0.05）,减少了心肌组织超氧化物的含量（P〈0.05）。AVLE治疗显着降低gp91phox的表达（P〈0.05）,使SOD活性增加（P〈0.05）,MDA水平显著降低（P〈0.05）。结论：AVLE通过抑制I/R心肌的氧化应激发挥心脏保护作用。

英文摘要：

Objective： To observe the effects of AVLE preconditioning on myocardial ischemia/reperfusion （MI/R） injury. Methods： Male Sprague-Dawley rats were divided into 3 groups randomly： sham, ischemia reperfusion and AVLE preconditioned group. The model of myocardial I/R injury in vivo was made by ligating the left anterior descending artery for 30 min followed by 4 h of reperfusion in SD rats. The hemodynamics were measured. The myocardial infarct size was measured by Evans blue and 2,3,5-triphenyltetrazolium chloride （TTC） staining. The level ofhyperoxide superoxide, malondialdehyde （MDA） and plasma creatine kinase （CK） were measured. The activities of ant~oxidant enzyme superoxide dismutase （SOD） and lactate dehydrogenase （LDH） were detected. The gp91~ were determined by Western Blot. Results： Compared with I/R group, the left ventricular ＋ dp/dtmax in AVLE preconditioned rats was increased （P〈0.05）. The percentage of area of necrosis was reduced （32.0±3.5% vs. 41.5±4.5%, P〈0.05）. The plasma CK and LDH levels were decreased to 1653±62 U/L and 2461 ±152 U/L （P〈0.05 vs. MI/R group）. AVLE preconditioning decreased superoxide accumulation （P〈0.05 vs. MI/R group）. AVLE treatment markedly decreased gp91~ expression （P〈0.05 vs. MI/R group）. The activity of SOD was increased （P〈0.05 vs. MUR group）. The level of MDA was decreased （P〈0.05 vs. MI/R group）. Conclusions： AVLE alleviates UR injury in myocardium by inhibition of excessive ERS.