参麦注射液对兔实验性心肌缺血预处理的实验研究

Experimental study on Shenmai Injection in rabbits with experimental myocardial ischemic preconditioning

目的观察参麦注射液对兔实验性心肌缺血预处理后血管内皮生长因子表达及氧化应激的作用,探讨其潜在机制。方法选取8只健康日本大耳白兔为对照组,另取24只随机分为缺血再灌注组、缺血预处理1组、缺血预处理2组,除对照组外,其余组均采用手术结扎左侧冠状动脉前降支45 min后再灌注60 min,反复3次以造成实验性心肌缺血再灌注损伤动物模型。缺血预处理1组、缺血预处理2组经耳缘静脉给予参麦注射液2 m L/(kg·d)、4 m L/(kg·d)连续缺血预处理7 d,对照组和缺血再灌注组给予等量生理盐水预处理7 d。采用双抗体夹心EUSA法测定兔缺血预处理7 d血清VEGF蛋白质及VEGF mRNA表达情况;酶联免疫吸附法检测兔血清乳酸脱氢酶(LDH)、血清总超氧化物歧化酶(T-SOD)及心肌丙二醛(MDA)、肌酸激酶同工酶(CK-MB)等指标。结果预处理7 d后缺血预处理1组、缺血预处理2组VEGF蛋白质及VEGF mRNA表达和T-SOD酶活性均高于缺血再灌注组(P均<0.05),MDA及LDH、CK-MB含量均低于缺血再灌注组(P均<0.05)。结论参麦注射液对兔实验性心肌缺血再灌注损伤有一定的保护作用。其作用机制可能是促进VEGF分泌,抑制心肌缺血时脂质过氧化,促进氧自由基清除酶清除氧自由基,加快兔缺血心肌血管内皮新生进而改善再灌注损伤后受损血管内皮功能。

Objective It is to observe the effect of Shenmai Injection on the expression of vascular endothelial growth factor and oxidative stress in rabbits with experimental myocardial ischemic preconditioning,and to explore its potential mechanism.Methods Eight Japanese white rabbits were selected as control group（ MG）,another 24 ones were selected and randomly divided into ischemia / reperfusion group（ IR group）,ischemic preconditioning group I（ group I）,ischemic preconditioning group II（ group II）,except MG group,the rabbits in the other three groups were operated by ligation of the left anterior descending branch of coronary artery for 45 min and reperfusion for 60 min,repeated 3 times to establish the animal models of experimental myocardial ischemia reperfusion injury. Group I and group II were given Shenmai Injection at the dose of 2 mL /（ kg·d） and 4 mL /（ kg·d） through ear vein for ischemic preconditioning for 7 days. MG group and IR group were given the same volume of normal saline. Serum VEGF protein and VEGF mRNA expression were determined by double antibody sandwich EUSA method before and after preconditioning; serum LDH,T-SOD and MDA,CK-MB in heart tissue were determined by enzyme linked immunosorbent assay test（ ELISA）. Results After 7 days＇ preconditioning,the levels of VEGF and VEGF mRNA,the activity of T-SOD were higher,while the contents of MDA,LDH and CK-MB in group I and group II than those in IR group（ all P 0. 05）. Conclusion Shenmai Injection has a protective effect on the rats with experimental myocardial ischemia reperfusion. The mechanism may be that it can promote the secretion of VEGF,inhibit lipid peroxidation induced by myocardial ischemia,promote oxygen free radical scavenging enzymes to clear oxygen free radicals,speed up vascular endothelial growth,thus to improve the impaired vascular endothelial functions after ischemia reperfusion injury.