Cannabidiol, as component of cannabis, can potentially hinder the rewarding impact of
drug abuse; however, its mechanism is ambiguous. Moreover, the nucleus accumbens (NAc), as a key area in the reward circuit, extensively receives dopaminergic projections from the ventral tegmentum area. To elucidate the role of accumbal D1 and D2
dopamine receptor families in
Cannabidiol's inhibitory impact on the acquisition and expression phases of
methamphetamine (MET), the conditioned place preference (
CPP) procedure as a common method to assay reward characteristics of drugs was carried out. Six groups of rats were treated by various doses of
SCH23390 or
Sulpiride (0.25, 1, and 4 μg/0.5 μL) in the NAc as D1 or D2
dopamine receptor family antagonists, respectively, prior to infusion of
Cannabidiol (10 μg/5 μL) in the lateral ventricle (LV) over conditioning phase in the acquisition experiments. In the second step of the study, animals received
SCH23390 or
Sulpiride in the NAc before
Cannabidiol (50 μg/5 μL) infusion into the LV in the expression phase of MET to illuminate the influence of
SCH23390 or
Sulpiride on the inhibitory impact of
Cannabidiol on the expression of MET-induced
CPP. Intra-NAc administration of either
SCH23390 or
Sulpiride impaired
Cannabidiol's suppressive impact on the expression phase, while just
Sulpiride could suppress the
Cannabidiol's impact on the acquisition phase of the MET-induced
CPP. Also, the inhibitory impact of
Sulpiride was stranger in both phases of MET reward. It seems that
Cannabidiol prevents the expression and acquisition phases of MET-induced
CPP partly through the dopaminergic system in the NAc.