Dopamine uptake inhibition is positively correlated with cocaine-induced stereotyped behavior

Fast-scan cyclic voltammetry on freely moving rats was used to determine whether a correlation exists between the increase in stereotyped behavior and dopamine (DA) uptake inhibition following cocaine (20 mg/kg, i.p.) administration. Voltammetric recordings were performed every 100 ms at a carbon fiber microelectrode, positioned in the nucleus accumbens. The present experiments revealed that the time course of the changes in Km strictly parallels the time course of the increase in stereotypy after cocaine. More importantly, the magnitudes of cocaine-stimulated stereotypy were positively and significantly correlated with the Km increases. Therefore, these data closely link the DA transporter inhibition with cocaine-induced stereotypy.