Effect of chronic cocaine on dopamine synthesis in the nucleus accumbens as determined by microdialysis perfusion with NSD-1015.

Reduced steady state formation of dihydroxyphenylalanine (DOPA) (47%) was found in the nucleus accumbens (N. ACC) of rats treated with ten days of repeated cocaine (10 mg/kg, i.p.) as compared to saline controls after NSD 1015 perfusion (10(-4) M) by microdialysis. In addition, prior to NSD 1015 perfusion, basal extracellular levels of the dopamine metabolite, dihydroxyphenylacetic acid (DOPAC) in the N. ACC were 33% lower in the chronic cocaine-treated animals. The results indicate the rate of dopamine synthesis in the N. ACC is significantly reduced by repeated cocaine administration.