Abstract: AimTo observe the effects of ouabain and aconitine on APD and ion channels in isolated guinea pig and rat ventricular myocytes; to elucidate the action mechanisms of these two drugs and set up new arrhythmic models on cellular level. MethodsIn isolated ventricular myocytes of guinea pig and rat, the effects of ouabain and aconitine on APD, I_Ca-L, I_k, I_to and I_k1 were observed using the whole cell patch clamp technique. ResultsOuabain (5 μmol·L^-1) obviously prolonged the APD₉₀, increased I_Ca-L, decreased I_k and I_k1 in guinea pig ventricular myocytes. Aconitine (1 μmol·L^-1) lengthened the APD₉₀, increased I_Ca-L, decreased I_to and increased I_k1 in rat ventricular myocytes. ConclusionThe targets on ouabain- and aconitine-induced arrhythmias included APD, I_Ca-L, I_k, I_to and I_k1. APD, I_Ca-L, I_k and I_to must be the powerful ones, both in arrhythmic and antiarrhythmic courses. The ouabain- and aconitine- induced arrhythmic models on cellular level were built to study the antiarrhythmic mechanisms of chemicals and evaluate new drugs. These two new-type models in vitro were stable, liable, repeatable and economic, which were superior to those typical models in vivo.