Puerarin blocks transient ourward K+ current and delayed rectifier K+ current in mice hippocampal CA1 neurons

AIM: To study the effects of puerarin (Pue) on I-A and I-K in mouse hippocampal neurons. METHODS: The whole cell patch clamp techniques were used. RESULTS: Pue reduced the amplitude of I-A and I-K, in a concentration-dependent, but not rate- or use-dependent manner (IC50 were 461 mu mol/L and 215 mu mol/L, respectively). Pue (0.5 mmol/L) shifted the steady state activation curves of I-A and I-K to positive and negative potentials (V-h about 20.6 mV and 28.6 mV) respectively, but inactivation curves of I-A, were not affected by Pue. CONCLUSION: Pue inhibited I-A and I-K in mouse hippocampal CA(1) neurons and its blocking effect on I-K was much stronger than on I-A.