Chronic lead exposure differentially affects dopamine transport in rat striatum and nucleus accumbens

Dopamine release and uptake were investigated in striatum and nucleus accumbens slices of rats chronically exposed to lead. No indication of altered endogenous dopamine release under basal or depolarized conditions was observed in both areas. On the other hand lead intoxication inhibited striatal dopamine uptake while stimulating it at the mesolimbic level. Cocaine binding, that is related to the uptake system, appeared to be down-regulated in the striatum and unaffected in the nucleus accumbens. The results suggest that chronic lead might interfere with dopaminergic transmission at the presynaptic level through specific and differential interactions with the uptake process depending on the area examined.