Fig. 3.

Effects of UMB24 and (±)-SM 21 on basal and cocaine-induced locomotor activity. Male, Swiss Webster mice were injected (i.p.) with UMB24 or (±)-SM 21 (0, 0.1 or 1 mg/kg, i.p.) alone or as a 15 min pretreatment to a locomotor stimulatory dose of cocaine (10 mg/kg, i.p.). Horizontal locomotor activity was quantified for 30 min using an automated activity monitoring system. UMB24 produced a significant locomotor depressant effect on its own (#p < 0.01), and also attenuated cocaine-induced locomotor activity (*p < 0.05). (±)-SM 21 had no significant effect of its own on locomotor activity, although it significantly attenuated cocaine-induced locomotor activity (*p < 0.05).