[Protective effect of ginsenoside Re on isoproterenol-induced triggered ventricular arrhythmia in rabbits]

To study the anti-arrhythmic efficacy of ginsenoside Re (GSRe) and its protective effects against myocardial injuries in rabbits with isoproterenol-induced triggered ventricular arrhythmia (TVA).

TVA model was prepared by intravenous injections of isoproterenol at a constant speed of 5 mg/kg/min. When TVA appeared, rabbits were randomly injected with GSRe (5, 10 or 20 mg/kg), verapamil (0.4 mg/kg) or placebo. The duration of maintaining sinus rhythm was observed. Meanwhile, isoproterenol was continued to be injected at a constant speed of 5 mg/kg/min. After 1 hr of isoproterenol injection, the rabbits were sacrificed. Cardiac muscles in the cuspidate position of the left ventricle were sampled for optical microscopy and electron microscopy.

GSRe and verapamil treatment restored sinus rhythm. The duration of sinus rhythm was 177.00+/- 5.66 s within 3 minutes in the verapamil treatment group and was 177.83+/- 5.31, 21.00+/- 2.83 and 4.50+/- 1.64 s, respectively, in the 20, 10 and 5 mg/kg GSRe treatment groups. Histopathologic examination demonstrated that GSRe treatment (20 and 10 mg/kg) alleviated myocardial injuries induced by TVA.

GSRe has anti-arrhythmic efficacies and protective effects against myocardial injuries in rabbits with TVA. It may therefore be a possible therapy for TVA.