Abstract:Objective: To investigate the effect of Cedemex on cAMP and cGMP contents in different brain regions in morphine withdrawal rats precipitated by naloxone. Method: A physical morphine dependent model of rats was established by subcutaneous injection of morphine in gradually increasing dosage within 7 days. cAMP and cGMP contents of VTA, cortex and hippocampus of the rat brains were determined by radioimmunoassay. Result: The morphine withdrawal symptoms of rats were relieved significantly by ig Cedemex. Compared with the controls, cAMP content in the region of VTA, cortex and hippocampus of the morphine dependent rats were significantly higher (P<0.05), while cGMP contents in those regions were significantly lower (P<0.05). cAMP contents in the area of VTA, cortex and hippocampus of the morphine dependent rats were significantly reduced, while cGMP contents were significantly increased by ig Cedemex. Conclusion: Cedemex may significantly attenuate the morphine withdrawal symptoms in rats. The mechanism of this effect may be related to adjusting the contents of cAMP and cGMP in some brain regions.