ABSTRACT
Objective: To observe the action of Salvia miltiorrhiza extracts (SmE2, liposoluble constituents) on the formation of physical dependence induced by morphine in mice and the effects of SmE2 on the production of cyclic adenosine monophosphate (cAMP) and nitric oxide (NO) in brain of morphine-dependent mice. Methods: Morphine-dependent mice model was established by sc injection of morphine at a gradual increasing dosage. The effect of SmE2 on the withdrawal symptoms induced by Naloxone in morphine-dependent mice was observed. cAMP and NO content in brain were determined through radioimmunoassay and nitrate reductase, respectively. Results: SmE2 (80 mg/kg) could remarkably reduce the withdrawal symptoms in morphine-dependent mice. The cAMP concentration in brain showed no obvious change in morphine-dependent mice treated with SmE2, but NO content in brain could significantly be reduced. Conclusion: SmE2 has effect on relieving the withdrawal symptoms in morphine-dependent mice with down-regulation of NO content in brain as possible mechanism.