伏隔核毁损对大鼠吗啡成瘾与戒断的影响及行为变化的研究

Effects of Nucleus Accumbens Lesion on the Morphine Addiction and Withdrawal Syndrome and the Behavioral Changes in Rats

目的：探讨毁损伏隔核对调控成瘾行为与戒断症状的有效作用及其对脑功能的影响，为临床戒毒治疗提供参考。方法：采用立体定位仪，电极毁损大鼠伏隔核，观察大鼠吗啡成瘾行为，戒断症状评分，并进行场地探索实验、Ｍｏｒｉｓ水迷宫实验。结果：毁损伏隔核组大鼠在全身吗啡给药成瘾过程中，基本不表现单纯吗啡成瘾组在此过程中的阳性反应，如兴奋、欣快、嗑笼、活动增多等。对吗啡耐受性较对照组差，单纯吗啡成瘾组与毁损组戒断总分分别为１１．５００±０．９１７和４．１６７±０．６０１，毁损组明显低于单纯吗啡成瘾组（Ｐ＜０．０１）。场地探索实验毁损组大鼠在行为灵活性和转换性上存在缺陷，探索主动性下降，动作和行为策略表现惰性。水迷宫实验毁损组在初期空间记忆的建立上存在缺陷。结论：伏隔核能调节吗啡的犒赏效应，破坏伏隔核戒断症状减轻。

Objective:We evaluated the neurobiologic effects of nucleus accumbens (NA) on morphine addiction, morphine withdrawal syndrom, and the behavioral changes on exploration and spatial memory after NA electrically spoiled.Methods:The NA of rats were lesioned electrically under the stereotaxic coordinates. The following experiments were taken addictive behavior observation, withdrawal evaluation, compartments investegation test and Morris water Maze test.Results: NA lesioned group didn't have the addictive symptoms, such as euphoria, exciting, hyperactivity and biting, with contrast to the addictive group. There was significant difference (P<0 01) between the two groups on the total withdrawal scores, (11.500±0.917) in the control group and (4.167±0.601) in the lesioned one. Compartments investigating experiment showed deficiency of the lesioned group on behavioral switching and strategic flexibility. There also had some deficiency of the NA. lesioned rats on the initial acquirement of spatial memory during the morris water maze. Conclusions: Nucleus acumbens was important in modulating the compensating effects of morphine addiction. The intensity of withdrawal symptoms was greatly reduced in NA. lesioned group. There were behavioral changes and spatial memory deficiency after NA lesion.