[The effect of tetrahydropalmatine on ouabain-induced delayed after depolarization and triggered ventricular arrhythmia]

Abstract

Objective: To study the effect and mechanism of tetrahydropalmatine (THP) ouabain-induced on delayed after depolarization (DAD) and anti-triggered ventricular arrhythmia in in-vivo rabbit heart.

Methods: 14 rabbits were divided into two groups at random, control group and THP group. The monophasic action potential (MAP) of right ventricule and the surface lead II electrocardiogram (ECG) were simultaneously recorded. The changes of MAP and ECG in the THP group were compared with those in the control group after administration of ouabain 150-170 ug/kg and before using the drug.

Results: The incidence and couple interval of DAD in the two groups had no apparent difference (P > 0.05) after administration of ouabain, but the amplitude of DAD and the incidence of triggered ventricular arrhythmia in the THP group were significantly lower than those in the control group (P < 0.05).

Conclusion: THP had the effect of decreasing the amplitude of DAD of rabbit heart induced by ouabain thus reducing the chance of triggered ventricular arrhythmia induced by DAD.