Effects of fourteen-day exposure to the herbicide atrazine on the nigrostriatal dopaminergic system of juvenile male C57BL/6 mice

The herbicide atrazine (ATR) is one of the most commonly used pesticides in the U.S. and it is a major ground water contaminant. Acute 14-day ATR administration to juvenile mice (up to 250 mg/kg BW) dose-dependently decreased striatal dopamine levels, as well as the levels of its metabolites for up to a week post treatment. ATR exposure also time- and dose-dependently decreased the number of the dopaminergic neurons in the substantia nigra (SN) and ventral tegmental area (with effects being more prominent in SN); the total number of neurons in these two areas was not affected by the ATR treatment. Thus, ATR appears to be selective dopaminergic toxicant by affecting primarily DA neurons.