Pyrethroids and the striatal dopaminergic system in vivo

1. Type I (permethrin and allethrin) or type II (cypermethrin and fenvalerate) pyrethroids caused 23-37% increases in the striatal content of the dopamine metabolite 3,4-dihydroxyphenylacetic acid (DOPAC). 2. Toxicity symptoms and increases in DOPAC were associated with higher brain concentrations for type I (2.6-5.8 micrograms/gm) than type II pyrethroids (0.4-0.6 micrograms/gm). 3. No specific difference in the interaction between type I and II pyrethroids and the striatal dopaminergic system were recognized.