2'-CH3-MPTP is an extremely potent dopaminergic neurotoxin, which lead to large decrements in the neostriatal concent of DA and a large loss in the capacity of a neostriatal synaptosomal preparations to take up [3H]DA. 2'CH3-MPTP-induced neurotoxicity, was attenuated by pretreatment of mice with dopamine uptake inhibitor, and non-specific MAO-A and MAO-B inhibitor, but not by a specific MAO-B inhibitor. The mechanism of toxicity is formation of a metabolite 2'CH3-MPP+, which is a potent inhibitor of mitochondrial respiration.