[Effect of zhigancao decoction containing serum on transient outward potassium current in isolated single ventricular myocyte of rabbits].

Objective: To investigate the effect of Zhigancao Decoction (ZD) containing serum on transient outward potassium current (I(to)) in isolated single ventricular myocyte of rabbits.

Methods: Single rabbit ventricular myocytes were isolated and divided into 6 groups, the normal group, the non-drug-containing serum group, and the ZD groups, they were treated with normal extracellular fluid alone or with ZD containing serum recording technique was used to observe the changes of I(to).

Results: After treated with 5%, 10%, 20% and 40% ZD containing serum, the I(to) was inhibited and its peak value dropped from (16.1 +/- 1.4) PA/PF to (13.9 +/-1.5) PA/PF, (11.8 +/- 1.9) PA/PF, (8.3 +/- 1.5) PA/PF and (8.2 +/- 1.2) PA/PF respectively, and the effect could be eliminated by elution.

Conclusion: ZD containing serum could inhibit the I(to) in isolated ventricular myocytes of rabbits in a concentration-dependent manner, which may be the mechanism of antiarrhythmic action of ZI).