海洛因成瘾复吸大鼠中脑腹侧被盖区、伏隔核神经元超微结构和全脑多巴胺递质含量变化的研究

RESEARCH ON NEURON ULTRASTRUCTURE IN THE VTA-NAc AND DA NEUROTRANSMITTER’S CHANGE IN THE BRAIN OF HEROIN ADDICTED AND READDICTED RATS

目的:模仿人类吸毒成瘾和脱毒治疗的临床实例,建立三个阶段的海洛因成瘾、复吸大鼠模型,对其中脑腹侧被盖区(VTA)、伏隔核(NAc)的超微结构和全脑(不含脑垂体)多巴胺(DA)的含量做动态研究,为深入研究海洛因成瘾复吸神经生物学及戒断治疗等奠定基础。方法:动物设对照组和模型组,三阶段各组大鼠均取VTA、NAc于电镜下观察超微结构改变,并测定各阶段各组大鼠全脑中的DA含量。结果:海洛因成瘾、复吸成瘾大鼠三阶段VTA、NAc神经元出现变性、凋亡、胀亡等超微结构改变,并随复吸次数增加而病变加重。三阶段海洛因成瘾复吸大鼠全脑DA含量均较对照组升高,并随复吸次数增加,DA含量增加幅度呈下降趋势。结论:神经元凋亡是海洛因成瘾、复吸成瘾致脑神经元死亡的主要形式,脑内DA含量变化与神经元超微结构改变出现一致性变化。复吸次数越多,脑损害越重。

Objective:To imitate the processes of human heroin addiction and abstention treatment,we set up the model of heroin addiction and readdiction .In the brain of heroin addicted and readdicted rats in 3 periods,we studied the neuron ultrastrusture changes of ventral tagmental area(VTA) and nucleus accumbens(NAc). At the same time ,we research on the amount of DA neurotransmitter so that we can make clear the dynamic trend of the brain lesions on heroin addicted rats in each period.Methods:Rats were randomly divided into control group and model group .The VTA-NAc from the animals of each period were observed by electronic microscope.DA neurotransmitter of the rats' brains(not including hypophysis)from each group in each period were analysed by means of fluorescence microspectro-photometry.Result:The ultrastrusture changes such as degeneration,apoptosis and oncosis appeared in the VTA-NAc of heroin addicted and readdicted rats' brains in all periods, and it showed the trend of aggravation by periodical pathological change. But the control groups didn't see any ultrastrusture changes. The DA neurotransmitter were up-regulated in the brains of the addicted and readdicted rats,but it showed the trend of decreasing by the increase of readdicted times.Conclusion:In the VTA-NAc of heroin addicted and readdicted apoptosis is the main way of neuronal death.The changes of DA neurotransmitter showed pathological accordingly.The lesions of brain were worse along with readdiction.