Effects of sodium ferulate on the ultrarapid delayed rectifier K + current in human atrial myocytes

Abstract

Objective To study the effects of sodium ferulate on the ultrarapid delayed rectifier K + current(I Kur) in human atrial myocytes. Methods Human atrial myocytes were isolated by enzyme dispersion method. I Kur in human atrial myocytes were recorded by using the whole cell patch clamp. The changes of I Kur were compared in the absence and the presence of sodium ferulate. Results There was no effect of 0.4 g/L sodium ferulate on I-V relation of I Kur. However, 0.4 g/L sodium ferulate inhibited I Kur to some degrees at each test pulse. The current densities of I Kur at +60 mV decreased from 4.997 ± 0.35 PA/PF to 3.331 ± 0.26 PA/PF( n =6, P < 0.05). The inhibitory effect was concentration-dependent. IC 50 was(0.41 ± 0.03)g/L and the Hill coefficient was 0.95 ± 0.05. Conclusion Sodium ferulate as a potassium channel blocker can inhibit I Kur in human atrial myocytes effectively.