Fig. 9.

VU0152099 and VU0152100 inhibit amphetamine-induced hyperlocomotor activity in rats without causing sedation. A, rats were pretreated for 30 min with vehicle or a 56.6 mg/kg dose of either VU0152099 or VU0152100 i.p. (data not shown). All rats received an injection of 1 mg/kg s.c. amphetamine, and locomotor activity was measured for an additional 60 min. Each point represents the mean of 8 to 16 rats. The error bars represent ± S.E.M. and are absent when less than the size of the point. Abscissa, dose of drug in milligrams per kilogram; ordinate, ambulations or total beam breaks per 5-min intervals; *, P < 0.05 versus veh + amphetamine control group, Dunnett’s test. B, lack of effect of VU0152100 on motor performance on the rotorod. After initial training trials, rats were pretreated for 30 min i.p. with vehicle or a dose of VU0152100, specifically 30, 56.6, or 100 mg/kg, and then the time each animal remained on the rotorod was recorded; animals not falling off the rotorod were given a maximal score of 85 s. Abscissa, dose of VU0152100 in milligrams per kilogram; ordinate, time spent on the rotorod in seconds. Each bar graph represents the mean of 8 to 10 rats. The error bars represent ± S.E.M.