A differential sex effect of amphetamine on exploratory behavior in maturing mice

The effects of amphetamine (5-20 mg/kg) were studied 60 min after injection in mice aged 2, 3, 4 and 6 weeks postpartum. Exploratory behavior as indicated by the "head poke" test was depressed at all ages, but appeared to be relatively uncomplicated by other effects at the 5 mg/kg dose. At 4 and 6 weeks control females showed significantly greater activity than males, and amphetamine produced a greater reduction for control levels than in males.