Reversal Effect Of Cryptotanshinone On Rewarding Properties Of Morphine And The Level Of Nitric Oxide In Morphine–sensitive Mice

subjective:To study the effect of Cryptotanshinone( icv and ip) on the acquisition and expression of morphine-induced conditioned place preference(CPP) and investigate the possible participation of nitric oxide in the acquisition of cpp in morphine-sensitized mice.Methods: (1) Mice are administrated (sc) morphine (6mg.kg-1) to established a morphine-induced conditioned place preference (CPP) model. (2) administration(ip) Cryptotanshinone at different dose to investigate its effect on the acquisition and expression of cpp in morphine-sensitive mice.(3) administration(icv) Cryptotanshinone at different dose to investigate its effect on the acquisition and expression of cpp in morphine-sensitive mice. (40) after cpp acquisition experiment the encephalon of mice are processed with NO kit .Results: (1)sc morphine 6mg/kg can establish a successful cpp model in morphine sensitive mice. (2) administration(ip) of Cryptotanshinone can dose-dependently inhibit the expression and acquisition of morphine-induced conditioned place preference in morphine-sensitive mice. (3) administration(icv) of Cryptotanshinone can dose-dependently inhibit the expression and acquisition of morphine-induced conditioned place preference in morphine-sensitive mice. (4) the level of nitric oxide change according to the administration(icv) of Cryptotanshinone at different dose during the acquisition of cpp in the morphine-sensitive mice.Conclusion : (1)Cryptotanshinone can dose-dependently inhibited the acquisition and expression of morphine-induced cpp, the result show that the Cryptotanshinone can reverse the rewarding properties of morphine and the active position probably located at the central nerve systems.(2)It propose that the anti-morphine effect of Cryptotanshinone have some relationship with its effect on changing the level of nitric oxide.