维生素E对大鼠心肌缺血-再灌注损伤的影响及机制探讨

Discussion on the influence and mechanism of vitamin E for myocardial ischemia-reperfusion injury of rats

目的探讨维生素E(Vit E)对大鼠心肌缺血-再灌注损伤(MIRI)的影响及机制。方法选取雄性健康Wistar大鼠60只,按照随机数字表法将其分为Vit E组、模型组和对照组,各20只。前两组在平左心耳下缘2 mm处结扎左冠脉前降支(LAD),30 min后松解结扣再灌注,复制MIRI模型;对照组只用丝线穿过LAD但不结扎。Vit E组在造模成功即刻肌注Vit E注射液4.5 mg/(kg·d),模型组、对照组术后肌注生理盐水4.5 mg/(kg·d),连续给药2周。检测并比较不同干预对各组抗氧化指标、缺血梗死程度及血流动力学指标的影响。结果 (1)与模型组比较,Vit E组左心室收缩末期压力(LVESP)明显升高,而左心室舒张末期压力(LVEDP)、血浆心钠素(ANP)明显降低,差异均有高度统计学意义(均P<0.01);(2)与模型组比较,Vit E组血清超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、一氧化氮(NO)活性/含量明显升高,而丙二醛(MDA)含量明显降低,差异均有高度统计学意义(均P<0.01);(3)与模型组比较,Vit E组梗死区(IA)面积、缺血危险区(IDA)面积、IA/IDA、IDA/LV均明显降低,差异均有高度统计学意义(均P<0.01)。结论 Vit E通过抗氧化应激、清除氧自由基作用改善大鼠MIRI,增强心脏功能。

Objective To discuss the influence and mechanism of vitamin E(Vit E)for myocardial ischemia-reperfu-sion injury(MIRI)of rats.Methods Sixty male health Wistar rats were selected and divided to Vit E group,model group and control group by random number table method,with 20 rats in each group.For the first two groups,the left anterior descending(LAD)in 2 mm near inferior margin of left auricle was ligatured,the knot was released after 30 min and taken reperfusion,then MIRI model was duplicated.For the control group,the silk yarn just was threaded through LAD rather than taken reperfusion.For Vit E group,4.5 mg/(kg*d)of Vit E injection was injected intramuscularly as soon as the molding was done;for the model group and control group,4.5 mg/(kg*d)of normal saline was injected in-tramuscularly after the operation,and the administration was conducted successively for 2 weeks.The influences of dif-ferent intervention on the antioxidant index,degree of ischemic infarction and hemodynamic index in each group were tested and compared.Results①Compared with model group,the left ventricular end systolic pressure(LVESP)in Vit E group was significantly increased,while the left ventricular end-diastolic pressure(LVEDP),atrial natriuretic peptide(ANP)were significantly decreased,the differences were highly statistically significant(P<0.01);②compared with the model group,the contents of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),nitric oxide(NO)activity in Vit E group were significantly increased,while the contents of malondialdehyde(MDA)were significantly decreased,the differences were highly statistically significant(P<0.01);③compared with model group,the area of infarction area(IA)and ischemia risk area(IDA),IA/IDA,IDA/LV in Vit E group were significantly decreased,the differences were highly statistically significant(P<0.01).Conclusion Vit E can improve the MIRI of rats and enhance the cardiac function through antioxidant stress,oxygen free radical removal effects.