Fig. 5.

Effects of combined pretreatment with the D₃R antagonist PG01037 and the D₁-like receptor antagonist SCH23390 on acute cocaine-induced locomotor activity in mice. a Total number of ambulations in the 60 min period following administration of 3.0 mg/kg cocaine. Thirty min prior to cocaine administration, animals had been injected with a combination of PG01037 (vehicle or 10.0 mg/kg) and SCH23390 (vehicle or 0.03 mg/kg SCH23390). b Conditions were identical to panel (a), with the exception that the dose of SCH23390 was increased 10-fold (vehicle or 0.3 mg/kg). Each data point represents mean ± SEM ambulations. All mice received all treatments (n = 8). Drug treatments are depicted in a table below each figure; a plus symbol indicates the active dose of the drug was administered, while a minus symbol indicates that its vehicle was administered. *p < 0.05, **p < 0.01, significant difference by Dunnett’s test compared to vehicle/vehicle/3.0 cocaine condition (empty bar)