ABSTRACT
The action of Tetrahydroberberine ( THB ) on arrhythmias of the animal models were studied. The arrhythmias induced by CaCl2 and BaCl2 were significantly counteracted by THB ( 30mg/kg ip ) without markedly changing the hemodynamic parameters of rats, but those evoked by aconitine or ouabain were not inhibited in rats or guinea pigs. THB ( 40mg/kg ip) was used to be prevented the arrhythmias induced by ischaemia-reperfusion of left anterior des-cending coronary artery in rats. It could decrease the incidence of vetricular fibrillation, short restored time of the sinus rhythm and diminish the mortality. THB ( 10mg/kg iv ) effectively reduced the incidence of the ventricular arrhythmia induced by hypothalamic electric stimulation in rabbits. The results indicate that THB possess significant antiarrhythmic effect. It may be concerned the action of THB to blok calcium entry