d-Amphetamine Conditioned Place Preference in Developing Mice: Relations With Changes in Activity and Stereotypies


    loading  Checking for direct PDF access through Ovid

Abstract

Conditioned place preference (CPP) with both visual and tactile cues, hyperactivity, and stereotypies produced by d-amphetamine (1–10 mg/kg ip, single dose) were studied in CD-1 mice at 2, 3, and 4 weeks from birth. CPP was shown from the youngest age onward in female mice and from 3 weeks in male mice. Hyperactivity was much more pronounced in postweanlings (3 and 4 weeks) than in preweanlings. Stereotypies (at 3.3 and 10 mg/kg) occurred from the youngest age and tended to peak at 3 weeks. Stereotypies may indicate a sickness experience or “poor welfare” (G. J. Mason, 1991; A. Wall, R. E. Hinson, E. Schmidt, C. Johnston, & A. Streather, 1990) due to an aversive component of amphetamine's action. Therefore, the delayed development of fully fledged amphetamine CPP, relative to cocaine CPP (G. Laviola, G. Dell'Omo, E. Alleva, & G. Bignami, 1992), may be due to an age-dependent diminution of the positive hedonic value of the former drug by negative effects that are minimal or absent in the case of the latter drug.

    loading  Loading Related Articles