CONDITIONED AVERSION AFTER DELAY PLACE CONDITIONING WITH AMPHETAMINE

Male, Sprague-Dawley rats received subcutaneous injections of either dextroamphetamine sulfate (AMP; 3.0 mg/kg) or vehicle [VEH (phosphate buffer); 1 ml/kg] immediately before (standard conditioning) or after (delay conditioning) conditioning sessions in a place-conditioning paradigm. AMP was paired for 4 conditioning sessions with one compartment of a three-compartment place-conditioning apparatus; VEH was paired for 4 conditioning sessions with another compartment. Animals were then tested for place preference or aversion by determining the proportion of time spent in each compartment during a 15-minute test session. Standard conditioning with AMP produced a place preference while delay conditioning produced a place aversion. Similar findings had earlier been reported from studies involving conditioned place preferences and aversions with nicotine. These studies demonstrated that the time of drug administration can be as strong a determinant of place-conditioning effects as the drug itself. © 1990.