Effect of short-term (acutely symptomatic,black bars), long-term (chronically symptomatic,white bars), and low-dose (asymptomatic,cross-hatched bars) MPTP exposure on presynaptic striatal dopamine uptake sites at three rostrocaudal levels [rostral (A), mid (B), and caudal (C)]. Results are expressed as the percentage change from the mean of eight control animals. All MPTP treatment groups at all rostrocaudal levels have highly significant (p < 0.01 vs normal controls) losses in specific [³H]mazindol binding at all striatal regions. The asymptomatic animals have significantly more [³H]mazindol binding than do the symptomatic animals in most ventral regions (^∧p < 0.01 vs asymptomatic group; #p < 0.05 vs asymptomatic group). CD, Caudate nucleus;DL, dorsolateral; DM, dorsomedial;N ACC, nucleus accumbens; VL, ventrolateral; VM, ventromedial.