Increased c-Fos expression in the medial part of the lateral habenula during cue-evoked heroin-seeking in rats

摘要: Conditioned environmental stimuli are known to be important determinants of drug seeking behavior. c-Fos, the protein product protooncogene is expressed in neurons when there drug-associated cue-induced drug-seeking behaviour. Therefore, its expression could serve as a marker regional neuronal activation. Using an extinction/reinstatement paradigm relapse animal model, we trained Sprague-Dawley rats nose-poke for i.v. heroin (0.05 mg/kg/infusion) either daily 4 h or 25 infusions 14 consecutive days. We then tested these animals cue-evoked heroin-seeking behavior after abstinence from self-administration Expression c-Fos was examined lateral habenula (LHb), region conveying information between limbic forebrain and midbrain. Findings showed that heroin-associated conditioned induce robust associated with increased immunoreactivity medial part LHb. This observation suggests involvement LHb mediating heroin.