Effect of Shensong Yangxin capsule treatment on sympathetic remodeling in rabbit myocardial infarction model

Objective:To investigate the influences of Shensong Yangxin Capsule on the ventricular sympathetic remodeling and susceptibility to ventricular arrhythmias.Methods:New Zealand rabbits were ligated with left anterior descending coronary artery to induce myocardial infarction model.All rabitts were randomly divided into SSYX group(treated with Shensong Yangxin Capsule 0.3g/kgd),MI group and Sham group(receiving thoracotomy without ligation).Programmed electrical stimulation was carried out after eight weeks and immunohistochemistry was applied to detect the sympathetic remodeling.Results:Ventricular arrhythmias incidence induced by programmed electrical stimulation was significantly higher in MI group than Sham group(46.7% vs.13.3%,P0.01).Shensong Yangxin Capsule treatment remarkably decreased ventricular arrhythmias incidence compared with MI group(26.7% vs.46.7%,P0.05).In MI group,density of tyrosine hydroxylase positive neural fibers at infarction border and left ventricular wall(3505±235 μm2/mm2,3179±190 μm2/mm2)were much higher in contrast to corresponding segments in Sham group(2533±173 μm2/mm2,2343±177 m2/mm2,P0.01),and the nerve distributiong was diversed.after Shensong Yangxin treatment,density of tyrosine hydroxylase positive neural fibers was reduced significantly campared with MI group(P0.01).Conclusion:Shensong Yangxin Capsule treatment is effective to reduced the incidence of ventricular arrhythmias after infarction,partly by improviong sympathetic remodeling.