The Inhibition Efficacy of Scopolamine on Reactivation of conditioned place preference in Morphine-Dependent Rats

Objective:To study inhibitory efficacy of scopolamine on reactivation of conditioned place preference(CPP)in morphine dependent rats.Methods:Morphine was administered by subcutaneous injection at gradually increasing dose(from10mg/kg to 60 mg/kg)for 6 days to establish morphine conditioned place preference .From day 7,the rats were administered normal sodium instead of morphine for 10 days to induce CPP extinction.The rats were given a single priming injection of morphine 4 mg/kg to reinstate the morphine CPP,some rats were treated by ip scopolamine(1mg/kg,2mg/kg,3mg /kg)prior to priming injection of morphine.Results:After priming injection of morphine 4 mg/kg,the time spent on the drug paired side was significantly reduced because of the treatment with scopolamine,compared with morphine group(P0.05).Conclusion:Scopolamine has some inhibitory effects on reactivation of conditioned place preference in morphine-dependent rats.