Dose-dependent and baseline-dependent conditioning with d-amphetamine in the place conditioning paradigm.
The place conditioning paradigm was used to evaluate the positively reinforcing effects of d-amphetamine. During conditioning, female rats were injected (IP) with saline or one of five doses (0.625-5 mg/kg) of d-amphetamine (d-A) and confined to the initially non-preferred side of the testing apparatus. The highest dose of d-A failed to produce a significant preference. The four middle doses of the drug induced a similar preference. A significant increase from baseline was observed on the 4th post-conditioning test day in the five drug groups and controls when given an injection of 1.5 mg/kg d-A 15 min prior to placement in the chamber. Control and drug groups were separated into high and low initial preference sub-groups. Place preferences were more readily induced by d-A in the subgroups with initially high baseline preferences. These findings as well as those of others led us to conclude that the place conditioning paradigm is a somewhat problematic way of measuring drug reinforcement and that the effects observed may not solely be the result of the conditioning of the drug's reinforcing properties to a particular environment.
Costello
N L
NL
Department of Pharmacology and Toxicology, Albany Medical College, NY 12208.
Carlson
J N
JN
Glick
S D
SD
Bryda
M
M
D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects*; D003913:Dextroamphetamine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D051381:Rats
D003913:Dextroamphetamine