Abolition of nomifensine-induced stereotypy after 6-hydroxydopamine lesions of ascending dopaminergic projections.

The effects of bilateral focal injections of 6-hydroxydopamine into the zona compacta of the substantia nigra (SNC) on nomifensine-induced stereotypy were examined in the rat. These lesions reduced neostriatal dopamine levels to less than 1 percent of control levels. They also abolished nomifensine-induced stereotyped behavior. It is suggested that nomifensine-induced stereotypy is mediated via a presynaptic action on dopamine uptake and release.