Abstract:The nerve cells were isolated acutely from the ventral nerve cord of the female spider of Pardosa pseudoannulata. The properties of the voltage-gated sodium ion channels of the acute separated neurons and the effects of cypermethrin on voltage-gated sodium ion channels were studied with whole-cell patch-clamp technique. The separated neurons were suitable to be used in the patch-clamp experimental research, but best be used in 4-6 hours after being isolated. Under whole-cell patch-clamp recording, sodium current (INa) was activated when the voltage was around -60mV, and the peak current occurred at about +10mV. INa was sensitive to tetrodotoxin. After treatment for the nerve cell with cypermethrin, the activated voltage of sodium channel shifted towards more negative (the value was around -70mV) and the peak current occurred at about +5mV. INa increased at the beginning, and then reduced rapidly. When nerve cells were treated with cypermethrin at different concentrations, there was no significant difference among INa at different voltages, but the duration to peak current became shorter with the increasing of cypermethrin concentrations.