Delta-9-tetrahydrocannabinol depresses inward sodium current in mouse neuroblastoma cells.

Whole-cell voltage-clamp techniques were used in order to define the effects of delta-9-tetrahydrocannabinol (THC) on the voltage-gated sodium current in neuroblastoma cells. With regard to the inward sodium current, THC decreased the peak amplitude and increased both the time to peak and tau for recovery. The reversal potential was unchanged, suggesting that channel selectivity for sodium was not altered by the drug. With regard to the outward sodium current, THC had no effect on the peak amplitude, time to peak or tau for recovery. This functional alteration of the voltage-gated sodium channel may contribute to the depressant effects of the cannabinoid.