Differential state-dependent modification of rat Nav1.6 sodium channels expressed in human embryonic kidney (HEK293) cells by the pyrethroid insecticides tefluthrin and deltamethrin

► We expressed rat Nav1.6 voltage-gated sodium channels in HEK293 cells. ► Tefluthrin and deltamethrin caused resting modification of Nav1.6 channels. ► Only deltamethrin exhibited use-dependent enhancement of modification. ► State-dependent effects of pyrethroids are influenced by the cellular context. ► Channels in HEK293 cells exhibit properties similar to native neuronal channels.