Inhibition of sodium channels in hippocampai pyramidal neurons by ketamine / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of ketamine on the voltage-gated sodium channels in hippocampal pyramidal neurons, trying to elucidate the possible mechanism of general anesthesia with ketamine.Methods Hippocampal pyramidal neurons were isolated from Wistar rats of 2 weeks old. Whole-cell patch-clamp recordings were made from cultured hippocampal pyramidal neurons before and after the application of ketamine The effect of ketamine on the sodium current amplitude and the kinetics of the channel were studied. Results The sodium channels were reversibly inhibited by ketamine in a dose-dependent manner. IC50 of ketamine was (794?21) ?mol/L.The hyperpolarizing shift of both steady-activation and steady-inactivation was observed.Conclusion Ketamine inhibits the voltage-gated sodium channels to some degree. Sodium channel inhibition may be involved in the mechanism of general anesthesia induced with ketamine.