参麦注射液对大鼠急性心肌缺血及eNOS mRNA表达的影响

目的：探讨参麦注射液(SMI)预处理可能对 大鼠急性心肌缺血及心肌内皮型一氧化氮合酶(eNOS)mRNA表达的影响。方法:大鼠随机分为对照组、模型组、处理组1和处理组2，应用异丙肾上腺素建立大鼠心肌 缺血模型,以心电图ST段抬高值作为心肌缺血指标，硝酸还原酶法测定血清和心肌的NO^-₂/NO^-₃，RT-PCR检测心肌eNOS mRNA表达。结果：模型组各时点的心 电图ST段均显著高于对照组，缺血20 min时达高峰，血清和心肌NO^-₂/NO^-₃含量及 心肌eNOS mRNA表达均低于对照组；两个处理组于缺血20、30、40 min时的心电图ST段抬高 幅度均显著低于模型组，血清和心肌NO^-₂/NO^-₃含量均显著高于模型组，心肌eNOS mRNA表达强于模型组；处理组1和处理组2比较，心电图ST段抬高幅度、血清和心肌的NO^-₂/NO^-₃含量及心肌eNOS mRNA表达差异均无显著。结论：参麦注 射液可能是通过促进心肌组织eNOS mRNA表达、增强eNOS活性而提高NO水平，达到抗心肌缺 血的作用。

Effect of shenmai injection on myocardial eNOS mRAN expression in myocardial ischemic rats

AIM: To study the effect of shenmai injection (SMI), a Chinese medicine, on nitric oxide and the expression of endothelial nitric oxide synthase (eNOS) mRNA in myocardium of rats with experimental myocardial ischemia. METHODS: Rats were randomly divided into four groups: control, model (ischemia), SMI 1 and SMI 2 group. A rat model of acute myocardial ischemia was established by isoprenaline treatment and the lift of ST segment in ECG was used as the index of myocardial ischemia. The nitric oxide (NO) contents in serum and myocardium and the expression of eNOS mRNA in myocardium were measured. RESULTS: Compared with control group, ST segment of ECG was significantly elevated 20, 30, 40 min after myocardial ischemia in model group, the lift peak of ST segment occurred 20 min after myocardial ischemia, the concentration of NO in the serum and myocardium and the expression of eNOS mRNA in myocardium were significantly lowered in model group. Compared with the model group, in SMI 1 group and SMI 2 group, the concentration of NO in the serum and myocardium and the expression of eNOS mRNA in myocardium were significantly increased, the lift of ST segment were significantly reduced 20, 30, 40 min after myocardial ischemia. Compared with SMI 1 group, the concentration of NO in the serum and myocardium and the expression of eNOS mRNA in myocardium and the lift of ST segment were not statistically different in SMI 2 group. CONCLUSION: Shenmai injection can increase the expression of eNOS mRNA in myocardium and the content of NO, and protect against myocardial ischemia in rats.