钩藤碱对苯丙胺依赖大鼠神经核团中NR2B mRNA表达的影响

目的研究钩藤碱对苯丙胺诱导的条件性位置偏爱大鼠伏核和杏仁核中NR2B mRNA表达的影响。方法将56只♂SPF级SD大鼠分为正常对照组、苯丙胺模型组、氯胺酮+苯丙胺组、钩藤碱低、中、高剂量+苯丙胺组和钩藤碱+生理盐水组,每组8只。按要求分别给予相应药物。d5用条件性位置偏爱箱观察大鼠在白箱中的停留时间,并用原位杂交技术对伏核和杏仁核NR2B mRNA表达进行检测。结果①连续4d给予苯丙胺2mg.kg-1建立了位置偏爱模型,氯胺酮及钩藤碱低、中、高剂量均可消除位置偏爱效应,随钩藤碱剂量增加效应加强,且钩藤碱自身无精神依赖性;②苯丙胺模型大鼠伏核和杏仁核NR2B mRNA表达较正常对照大鼠明显增加,氯胺酮及中、高剂量钩藤碱抑制NR2B mRNA的表达,低剂量无明显影响。钩藤碱本身不影响正常大鼠NR2B mRNA的表达。结论伏核和杏仁核NR2B mRNA的表达参与了钩藤碱抗苯丙胺依赖作用的分子生物学机制。

The effect of rhynchophylline on NR2B mRNA expression in nucleus accubems and amygdaloid of amphetamine-dependent rats

Aim To study the effect of rhynchophylline on NMDA receptor 2B subunit(NR2B) mRNA expression in the nucleus accumbens(NAc) and amygdala(Amy) of amphetamine-induced condictioned place preference(CPP) rats.Method 56 male SPF grade Sprague-Dawley rats were randomly divided into control group,amphetamine-induced model group,model group with ketamine,model group with low,middle,high dose of rhynchophylline,and control group with rhynchophylline(n=8 for each group) The time of rats' staying in white compartment was measured in the 5th day,then NR2B mRNA expression in NAc and Amy of each rat was detected with in situ hybridization technology.Results The rats exhibited CPP after treated with 2 mg·kg-1·d-1 amphetamine for 4 d.Ketamine and rhynchophylline eliminated CPP effect,and the effect of rhychophylline showed a dose-dependence.In amphetamine-induced model group,NR2B mRNA expression in NAc and AMY of rats was significantly increased.Ketamine,middle and high dose of rhynchophylline blocked the increase of NR2B mRNA expression induced by amphetamine.Rhynchophylline had no effect on the basal level of RN2B mRNA expression in normal rats.Conclusion Inhibition of NR2B mRNA expression in NAc and AMY may contribute to the antagonistic effect of rhychophylline on amphetamine-induced CPP.