【摘要】 目的探讨双侧毁损伏隔核对吗啡给药大鼠觅药行为及大鼠探索行为的影响,为临床治疗药物依赖提供依据。方法在脑立体仪的引导下,用微量加样器将6-羟多巴胺缓慢注射入所有毁损组大鼠双侧伏隔核,而未毁损组注射等量生理盐水。以条件性位置偏爱实验为评价指标,评价双侧毁损伏隔核对吗啡给药大鼠觅药行为的影响;以场地探索实验为评价指标,评价双侧毁损伏隔核对大鼠探索行为的影响。结果在条件性位置偏爱实验中,单纯给药组实验后第1天、第4天、第7天、第10天在白盒里停留时间的对数平均值分别为5.54±1.30、5.46±1.62、5.64±1.31、5.49±1.32,与毁损给药组、单纯毁损组、对照组相比较差异有显著性(P<0.05),而其他三组之间差异无显著性;在场地探索实验中毁损组A室直立数,直立时间前2天低于对照组,其运动方格数却高于对照组(P<0.05或P<0.01)。而毁损组大鼠进入B室潜伏期却高于对照组(P<0.05或P<0.01),并且毁损组大鼠对新物的探索时间高于对照组(P<0.05)。而第9天撤除新物后毁损组大鼠对新物的探索时间却低于对照组(P<0.05)。结论伏隔核中的多巴胺系统在精神依赖(大鼠表现为条件性位置偏爱)形成过程中起关键性作用;化学毁损伏隔核中的多巴胺系统能够影响吗啡给药大鼠的觅药行为,对大鼠运动探索能力也有一定影响。更多还原

【Abstract】 ObjectiveTo explore the effects on behavior to look for drug in the rats with morphine and on exploratory behavior in the rats with after bilateral nucleus accumbens(NAc).MethodsUnder the guidance of the brain solid positioner, 6-hydroxydopamine were slowly injected into the bilateral NAc of all the impaired rat groups with a micropipette, and the unimpaired groups were injected saline. The effects on behavior to look for drug and exploratory behavior of the rats were evaluated by means of conditioned place preference(CPP) test and compartments investigation test respectively. ResultsStaining slices of brain tissue showed the dopamine systems in NAc were destroyed by 6-hydroxydopamine. In the CPP test, the simple morphine group had no significant difference with the other three groups, the simple impaired group, the control group and the impaired group with morphine( P <0.05), which had no difference with each other. The CPP of simple morphine group increased, and then decreased in the process of natural withdraw.The compartments investigation experiment showed deficiency of the NAc lesioned rats on behavioral switching and strategic flexibility.ConclusionsChemically impairing dopamine systems in the NAc affects the rats with morphine to form CPP and exploratory behavior,thus the formation of psychological dependence.更多还原