Effects of Wenxin Keli on the Action Potential and L-Type Calcium Current in Rats with Transverse Aortic Constriction-Induced Heart Failure

Abstract EN

Objective.

We investigated the effects of WXKL on the action potential (AP) and the L-type calcium current (ICa-L) in normal and hypertrophied myocytes.

Methods.

Forty male rats were randomly divided into two groups: the control group and the transverse aortic constriction- (TAC-) induced heart failure group.

Cardiac hypertrophy was induced by TAC surgery, whereas the control group underwent a sham operation.

Eight weeks after surgery, single cardiac ventricular myocytes were isolated from the hearts of the rats.

The APs and ICa-L were recorded using the whole-cell patch clamp technique.

Results.

The action potential duration (APD) of the TAC group was prolonged compared with the control group and was markedly shortened by WXKL treatment in a dose-dependent manner.

The current densities of the ICa-L in the TAC group treated with 5 g/L WXKL were significantly decreased compared with the TAC group.

We also determined the effect of WXKL on the gating mechanism of the ICa-L in the TAC group.

We found that WXKL decreased the ICa-L by accelerating the inactivation of the channels and delaying the recovery time from inactivation.

Conclusions.

The results suggest that WXKL affects the AP and blocked the ICa-L, which ultimately resulted in the treatment of arrhythmias.