中药活血化瘀汤对急性心肌缺血ET和NO及其相关酶和mRNA表达的影响

目的:探讨中药活血化瘀汤对急性心肌缺血兔循环一氧化氮(NO)和内皮素(ET)的浓度及其相关酶(ECE)和eNOSmRNA表达的影响。方法:结扎麻醉兔的冠状动脉左前降支中段,造成实验性急性心肌缺血的模型,采用动物随机分5组,采用放射免疫法和比色法测定NO、ET。取缺血区和非缺血区心肌组织进行原位杂交观察ECE和eNOS的基因表达与分布。结果:急性心肌缺血时ET明显升高,NO明显下降,eNOS明显下降,ECE的mRNA表达明显增多,eNOS的mRNA表达明显降低,中药活血化瘀汤可以提高NO浓度和降低ET水平,降低ECE的mRNA的表达,增加eNOS的mRNA表达。结论:活血化瘀汤有较好的抗心肌缺血作用,提高NO水平,增加eNOS的mRNA表达,降低ET水平,降低ECE的mRNA的表达,维持ECEmRNA和eNOSmRNA之间的平衡,从而增加对缺血心肌的保护作用。

Effect of HXHY on ET, NO and ECE mRNA, eNOS mRNA Gene Expression in Acute Myocardial Ischemia

Objective:The changes of circulating nixic oxide(NO)and endothelin(ET)and ECE mRNA and eNOSmRNA in acute myocardial ischemic rabbits.Methods:The animal model of acute myocardial ischemia was reproduced in anesthetited rabbit by ligating the left coronary artery at the middle of anterior descending branch.The serum NO and plasma ET were determined by colorimetry and radioimmunoassay respectively,ECE mRNA and eNOS mRNA expression and distribution was observed by in situ hybridization with ischemic area and unischemic area of myocardium.The rabbits were randomly divided into five groups.Results:As the time of occulusion extended the serum gradually decreased and the plasma level of ET elecated significantly.The hightest ECE mRNA level and lowest eNOS mRNA was shown in the ischemic area of myocardium.The decoction for HXHY can increase the level of NO and eNOS mRNA expression and decrease the level of ET and ECE mRNA expression.Conclusions:HXHY have the better effect of anti-myocardial ischemia.It can increase the level of NO and eNOS mRNA expression and decrease the level of ET and ECE mRNA expression,so as to keep a balance between them.By this way,it could be effective in protecting ischemic myocardium.