Quinpirole-induced locomotor activity in 12 10-min blocks (a) or in 120 min (b) in the quinpirole-induced hyperlocomotion test. The test was conducted two days after the last aripiprazole (ARI) challenge test. All rats were injected with quinpirole (1.0 mg/kg, subcutaneously (sc)) and then measured for motor activity for 120 min. All data are expressed as mean + standard error of the mean (SEM) in 12 10-minute blocks. PCP: phencyclidine; VEH: vehicle. *p<0.05, **p<0.01, ***p<0.001 for comparison to the VEH+VEH group; #p<0.05, ##p<0.01 for comparison to the VEH+PCP group; $p<0.05, $$p<0.01 for comparison to the ARI 3.0+PCP group; &p=0.05 for comparison to the ARI 10.0+PCP group.