Effects of benzyltetrahydropalmatine on delayed afterdepolarization and Triggered activity and on his-bundle Electrogram and ECG in animal experiment

Abstract

Standard microelectrode techniques were used to study the effects of benzyltetrahydropalmatine (BTHP) on ouabain-induced delayed afterdepolarization (DAD) and triggered activity in isolated guinea papillary muscles. The results indicate that ouabain-induced DAD and triggered activity were abolished by BTHP 100 μmol/L. In anesthetized rabbit ECG heart rate was reduced in a dose-dependent manner from control value of 288±14 to 261±14 (BTHP 5 mg/kg) and 226±36 bpm (BTHP 10 mg/kg). P-R interval was prolonged. In His-bundle electrogram, H-V interval and V duration were not affected, but A-H interval was prolonged from 41±3 to 45±5 ms.

Keywords

berbines / tetrahydropalmatine / electrophysiology / bundle of His / electrocardiography

References

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