Intra-BLA or intra-NAc infusions of the dopamine D3 receptor partial agonist, BP 897, block intra-NAc amphetamine conditioned activity

Recent studies have shown that both systemic and intra-nucleus accumbens (NAc) or intra-amygdala administration of dopamine D-3 receptor ligands modulate reward-related learning. A previous study (H. Aujla, H. Sokoloff, & R. J. Beninger, 2002) showed that systemic administration of the partial dopamine D3 receptor agonist BP 897 selectively blocked the expression, but not the acquisition, of amphetamine-conditioned activity. This suggested the hypothesis that intra-NAc or intra-basolateral amygdala (BLA) BP 897 would attenuate the expression, but not the acquisition, of amphetamine-conditioned activity. Rats were habituated to activity-monitoring chambers for 5 days, for 1 hr each day. Conditioning occurred on the next 3 days, followed by a single 1-hr test session. Intra-NAc or intra-BLA infusions of BP 897 during test, but not during conditioning, attenuated intra-NAc amphetamine conditioned activity. Results indicate that the ability of BP 897 to attenuate the expression of conditioned activity is mediated in part by the NAc and BLA.