RELEASE OF NEUROTRANSMITTERS FROM RABBIT BRAIN SLICES BY FENVALERATE

摘要

Pyrethroid insecticides exert a direct neurotoxic effect on excitable tissues and recent studies strongly implicate the sodium channel of the nerve membrane as the primary site of pyrethroid action (Narahashi, T. Neurotox. 6:3-22, 1985). The actions of pyrethroids have been characterized in the invertebrate nervous system, but less is known of their effects in mammalian brain. Type II pyrethroids produce a poisoning syndrome in mammals that is characterized by hind limb rigidity and choreoathetosis. Electroencephalographic studies have suggested that these agents may exert a selective action in the region of the basal ganglia (Ray, D.E. Neurobehav. Toxicol. Teratol. 4:801-804, 1982). We have recently demonstrated that the type II pyrethroid, fenvalerate, evokes a calcium-dependent, tetrodotoxin-sensitive release of radiolabeled dopamine and acetylcholine from rabbit striatal slices (Eells, J.T. and Dubocovich, M.L. Pest. Sci. 16:439-440, 1985). These findings are consistant with the behavorial and EEG studies in pyrethroid-intoxicated rats. The purpose of this investigation was to compare fenvalerate-evoked neurotransmitter release in the striatum with other brain regions.