Developmental changes in amphetamine-induced taste aversions.

In this study a conditioned taste aversion paradigm was employed to examine the ontogenetic trend in psychopharmacological responsiveness to amphetamine among infant (18 days of age), periadolescent (35 days of age), and young adult (52 days of age) rats. The ability of amphetamine to alter taste preference increased with dosage level and this effect interacted with age. Infant rats demonstrated greater sensitivity to the taste aversion inducing properties of amphetamine than either periadolescent or young adult animals. In contrast, periadolescent animals demonstrated a marked resistance to amphetamine's taste aversion inducing properties when compared with either infant or young adult animals. This developmental pattern in amphetamine drug responsiveness seen utilizing the taste aversion paradigm parallels the previously examined ontogenetic trend in amphetamine response using locomotor activity as a response measure.