Effect of phosphocreatine on transient outward potassium current in ischemic ventricular mid-myocardial cells of rats / 中国病理生理杂志

ABSTRACT

AIM: To determine the effect of exogenous phosphocreatine (PCr) at different concentrations on transient outward potassium (Ito) current in rat ischemic ventricular mid-myocardial (M) cells and to explore the antiarrhythmia mechanism in the treatment of ischemic heart disease. METHODS: M cells were isolated enzymatically from left ventricular mid-myocardium of rats. Peak Ito current was recorded by patch-clamp technique in the whole-cell configuration when M cells were superfused with normal Tyrode solution,simple ischemic solution,and simulated ischemic solution containing PCr at concentrations of 5,10,20 and 30 mmol/L for 10 min. RESULTS: Peak Ito current density of M cells superfused with simple simulated ischemic solution was significantly reduced by (76.1±6.3)% (P0.05). CONCLUSION: PCr reverses the inhibition of Ito current under ischemic condition in M cells,which may be the mechanism responsible for arrhythmia prevention in ischemic heart disease. PCr at concentrations of 0～10 mmol/L exerts significant dose-effect relationship.