Dissociation between behavioral effects of (-)-N-(2-chloroethyl)-norapomorphine and D2 dopamine receptor-like...

Low doses of d-amphetamine (1.0 mg/kg) can reduce the spontaneous hyperactivity of BALB/cJ mice. Amphetamine-induced hypolocomotion can be antagonized by NCA and sulpiride pretreatment, suggesting that this is a dopaminergic phenomenon. However, behaviorally active doses of NCA do not alter brain D2 dopamine receptor binding in either mice or rats. NCA also did not induce stereotypy/catalepsy or affect apomorphine-induced stereotypy. The results suggest that another type of dopamine receptor may mediate the behavioral effects of amphetamine and NCA.