Abstract
Rationale. It has been suggested previously that conditioned effects on drug-seeking behaviour are in part mediated through glutamatergic neurotransmission.
Objectives. To optimise a second-order schedule of IV cocaine reinforcement in Wistar rats and investigate the effects of the systemic AMPA/kainate receptor antagonist CNQX on cocaine-seeking behaviour under this schedule.
Methods. Free-feeding Wistar rats were trained to respond for an IV cocaine infusion (0.25 mg/infusion) under a FI15 min(FR7:S) schedule, whereby the completion of FR7 responses led to the presentation of a conditioned stimulus (CS). After two 15-min fixed intervals, rats were allowed to respond for cocaine under an FR4(FR7:S) second-order schedule for another 120 min. After acquisition of stable responding, the cocaine unit dose was increased to 0.50 mg/infusion. The effects of CNQX (0, 0.75, 1.5, and 3 mg/kg IP) on cocaine seeking were then examined using a within-subjects design.
Results. Increasing the cocaine unit dose increased responding during the first and second intervals, with a decrease in the latency to the first CS. CNQX decreased the number of cocaine responses in a dose-dependent manner during the first 15-min cocaine-free interval, but did not affect cocaine responding during either the second interval or the latter part of the session under the FR4(FR7:S) schedule. In the locomotor activity test, reductions in rearing were produced by higher CNQX doses than those that attenuated significantly responding during the first fixed interval.
Conclusions. These results suggest that AMPA/kainate receptors are involved in mediation of cocaine-seeking behaviour controlled partly by cocaine-associated cues.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
Author information
Authors and Affiliations
Additional information
Electronic Publication
Rights and permissions
About this article
Cite this article
Bäckström, P., Hyytiä, P. Attenuation of cocaine-seeking behaviour by the AMPA/kainate receptor antagonist CNQX in rats. Psychopharmacology 166, 69–76 (2003). https://doi.org/10.1007/s00213-002-1312-y
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s00213-002-1312-y