松养心胶囊对兔心肌梗死后酪氨酸羟化酶mRNA表达及室性心律失常的影响

Influences of Shensong Yangxin capsule on expression of tyrosine hydroxylase mRNA and inducible ventricular arrhythmias after myocardial infarction in rabbits

目的通过制备新西兰兔心肌梗死模型,检测心肌酪氨酸羟化酶(tyrosine hydroxylase,TH)mRNA表达水平,探讨参松养心胶囊改善心肌梗死后心肌电生理,减少室性心律失常的可能机制。方法结扎30只新西兰兔冠状动脉前降支制备心肌梗死模型,随机分为心肌梗死组(MI组,n=15)和心肌梗死+参松养心胶囊组(参松养心胶囊0.3g/kg.d,SSYX组,n=15)。另取15只兔作为假手术组(Sham组,n=15),冠状动脉穿线但不结扎。术后8周行程序电刺激诱发室性心律失常试验。并通过RT-PCR方法检测心肌TH mRNA表达水平。结果 MI组室性心律失常诱发率明显高于Sham组(46.7%比13.3%,P<0.01);参松养心胶囊干预后室性心律失常诱发率降低至26.7%。MI组梗死灶周及非梗死左室游离壁TH mRNA水平分别为(3.176±0.099,2.028±0.072),显著高于Sham组相应部位TH mRNA表达(0.958±0.051,0.960±0.054,P<0.01)。经参松养心胶囊治干预后8周SSYX组相应部位TH mRNA表达有所降低(1.768±0.113,1.246±0.142),与MI组相比具有明显统计学差异(P<0.05)。结论参松养心胶囊可降低兔心肌梗死后心肌TH mRNA表达水平,降低室性心律失常的诱发率。

Objective：To investigate the influences of Shensong Yangxin Capsule on the expression of tyrosine hydroxylase mRNA and susceptibility to ventricular arrhythmias in rabbit myocardial infarction models. Methods ： Left anterior descending coronary artery was ligated to induce myocardial infarction in 30 rabbits, then they were randomly divided into SSYX group （ treated with Shensong Yangxin Capsule, n = 15） and MI group （ n = 15 ）. Sham operation was performed in 15 control rabbits. After eight weeks, ventricular arrhythmias were induced by programmed electrical stimulation, and the expression of tyrosine hydroxylase mRNA was studied using real time fluorescent quantitation RT - PCR techniques. Results ： ventricular arrhythmias incidence induced by programmed electrical stimulation was significantly higher in MI group than Sham group（46.7% vs. 13.3%, P 〈 O. 01 ）. Shensong Yangxin Capsule treatment obviously decreased ventricular arrhythmias incidence compared with MI group （26.7% vs. 46.7%, P 〈 0.05 ）. The expression of tyrosine hydroxylase mRNA at infarction border and left ventricular wall in M] group were much higher than corresponding segments in sham group （P 〈 0.01 ）. After eight -week Shensong Yangxin Capsule treatment, the expression of tyrosine hydroxylase mRNA was reduced remarkably campared with MI group（P 〈 0.05）. Conclusion： In rabbit myocardial model, Shensong Yangxin Capsule treatment reduceds expression of tyrosine hydroxylase mRNA, and decrcsases incidence of ventricular arrhythmias.