Different effects of short- and long-term treatment with imipramine on the apomorphine- and food-induced place preference conditioning in rats.
The effect of imipramine (IMI) on the rewarding properties of pharmacological and natural reinforcers was studied with a place preference paradigm. The pairing of distinctive environmental stimuli with either injection of different doses of apomorphine (APO) or presentation of food to hungry rats resulted in a conditioned preference for those stimuli. The development of APO- and food-induced place preference was prevented by short-term administration of IMI. In contrast, long-term pretreatment with IMI significantly potentiated the APO- and food-induced conditioned effect. In separate experiments aversive properties of IMI by itself were also found, as the conditioned avoidance response to the environmental stimuli paired with administration of single doses of IMI was demonstrated. The results indicate an enhancing effect of the long-term IMI administration on the dopamine-mediated reward functions and the rewarding value of natural reinforcers.
Papp
M
M
Polish Academy of Sciences, Institute of Pharmacology, Krakow, Poland.
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001362:Avoidance Learning / Q000187:drug effects; D003216:Conditioning, Operant / Q000187:drug effects; D005502:Food; D007099:Imipramine / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D012054:Reinforcement, Psychology
D001058:Apomorphine; D007099:Imipramine