RESUMEN
AIM To explore the effects of sinomenine (Sin) on psychic dependence induced by morphine (Mor) in mice and its relation to the cAMP content of the cerebral cortex. METHODS A biased procedure induced the strong place preference. The effect of Sin (10, 30, 60 mg?kg -1 , ip) on the rewarding property of morphine was observed in a conditioned place preference(CPP) paradigm in mice,at the same time, the change of cAMP content in cerebral cortex was measured by the radioimmunoassay(RIA). RESULTS Sin significantly shortened the time of staying in morphine-pair compartment and lowered the cAMP level of mice. CONCLUSION Sin could attenuate effects of psychical dependence induced by Mor, its mechanism may be related to decrease of cAMP level in the brain, and Sin did not display psychical dependence in the experiment.