Low and high locomotor responsiveness to cocaine predicts intravenous cocaine conditioned place preference in male Sprague-Dawley rats
- PMID: 17250883
- PMCID: PMC2712248
- DOI: 10.1016/j.pbb.2006.12.005
Low and high locomotor responsiveness to cocaine predicts intravenous cocaine conditioned place preference in male Sprague-Dawley rats
Abstract
Outbred, male Sprague-Dawley rats can be classified as either low or high cocaine responders (LCRs or HCRs, respectively) based on cocaine-induced locomotor activity in an open-field arena. This difference reflects cocaine's ability to inhibit the striatal dopamine transporter and predicts development of sensitization. To investigate the relationship between initial cocaine locomotor responsiveness and cocaine reward, here we first classified rats as either LCRs or HCRs in a conditioned place preference (CPP) apparatus. Subsequently, we conducted cocaine conditioning trials, twice-daily over 4 days with vehicle and cocaine (10 mg/kg, i.p. or 1 mg/kg, i.v.). When cocaine was administered by the i.p. route, similar to previous findings in the open-field, LCRs and HCRs were readily classified and locomotor sensitization developed in LCRs, but not HCRs. However, cocaine CPP was not observed. In contrast, when cocaine was administered by the i.v. route, the LCR/HCR classification not only predicted sensitization, but also CPP, with only LCR rats exhibiting sensitization and cocaine conditioning. Our findings show that the initial locomotor response to cocaine can predict CPP in male Sprague-Dawley rats under conditions when place conditioning develops, and that LCRs may be more prone to develop conditioning in the context of cocaine reward.
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References
-
- Bardo MT, Bevins RA. Conditioned place preference: what does it add to our preclinical understanding of drug reward? Psychopharmacology. 2000;153:31–43. - PubMed
-
- Brabant C, Quertemont E, Tirelli E. Evidence that the relations between novelty-induced activity, locomotor stimulation and place preference induced by cocaine qualitatively depend upon the dose: a multiple regression analysis in inbred C57BL/6J mice. Behav Brain Res. 2005;158:201–210. - PubMed
-
- Briegleb SK, Gulley JM, Hoover BR, Zahniser NR. Individual differences in cocaine- and amphetamine-induced activation of male Sprague-Dawley rats: contribution of the dopamine transporter. Neuropsychopharmacology. 2004;29:2168–2179. - PubMed
-
- Cain ME, Smith CM, Bardo MT. The effect of novelty on amphetamine self-administration in rats classified as high and low responders. Psychopharmacology. 2004;176:129–138. - PubMed
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