吗啡成瘾大鼠伏核毁损术后行为学改变与脑内单胺类神经递质变化的相关性

The relationship between the level of monoamine neurotransmitters and the change of ethology after nucleus accumbence lesioned in morphine-addicted rats

目的探讨吗啡成瘾大鼠伏核毁损术后行为学改变与脑内单胺类神经递质变化的相关性。方法通过给大鼠每日2次腹腔注射吗啡,逐日递增吗啡用量,制作急性吗啡成瘾模型。用立体定向技术电极毁损伏核,对比毁损前后吗啡成瘾大鼠的行为学变化;高效液相色谱-荧光检测法测定脑内不同结构的单胺类神经递质含量,比较毁损前后递质含量的变化。综合分析吗啡成瘾大鼠伏核毁损术后行为学改变与脑内单胺类神经递质变化的相关性。结果急性吗啡成瘾模型制模成功率较高,大鼠成瘾前后以及毁损术后行为学变化明显,毁损伏核后可缓解成瘾大鼠的戒断症状。毁损伏核后大鼠相关脑区多巴胺、去甲肾上腺素含量下降,5-羟色胺含量升高,真毁损组较假毁损组的变化明显(P<0.01)。结论吗啡成瘾大鼠立体定向毁损伏核后相关脑区单胺递质含量的变化与毁损术前后行为学的改变有一定的相关性。

Objective To investigate the relationship between the level of monoamine neurotransmitters and the change of ethology after nucleus accumbence lesioned in morphine-addicted rats. Methods An acute morphine-addicted rat mode was made with morphine by abdominal cavity injection. The interval of the injection is 12 hours. The dose of injection was added by daily from 5 mg/kg to 90 mg/kg within 10 days. Before and after stereotaxic lesion, the level of monoamine neurotransmitters in different brain regions was detected by a fluorescence detector （ high performance liuid chromatography ）. The relationship between the monoamine neurotransmitters and ethological changes was analyzed after nucleus accumbence lesioned in the experiment rats. Results There was a high successful rate in making acute morphine-addicted rats, and remarkable ethological changes in morphine-addicted rats before and after stereotaxic lesion. There was significant difference in ethological changes between nucleus accumbens- lesioned group and nucleus accumbens pseudo-lesioned group. After nucleus accumbence lesioned, the abstinence syndrome could lessen. The levels of DA, NE ,5-HT in the regions of prefrontal cortex, hippocampus and ventral tegmental area were obvious changed compared with the unlesioned group in morphine-addicted rats （P〈 0.01）. Conclusion There may be some relationships between changes of ethology and the levels of monoamine neurotransmitters in the morphine-addicted rat.