抑郁症大鼠海马5-羟色胺含量及中缝核色氨酸羟化酶-2表达变化的研究  

The expression of TPH2 in median raphe nuclei in depression model rats

作　　者：肖爱娇[1] 韩志芬[2] 黄号斌[2] 庄剑青[2] 

机构地区：[1]江西中医学院生理学教研室,南昌330006 [2]上海中医药大学教学实验中心

出　　处：《中华精神科杂志》2008年第3期180-183,共4页Chinese Journal of Psychiatry

摘　　要：目的观察抑郁症模型大鼠海马5-羟色胺（5-HT）含量及其合成限速酶——色氨酸羟化酶-2（TPH2）表达的变化。方法雌性Sprague—Dawley大鼠20只，随机分为正常组和模型组；模型组给予孤养加21d慢性不可预见性温和应激（以下简称应激）。采用旷场试验测试大鼠的行为学变化；高效液相色谱-电化学法测定大鼠海马5-HT的含量；逆转录聚合酶链反应技术检测中缝核TPH2mRNA的表达量；荧光免疫组化检测中缝核TPH2蛋白的表达。结果应激第21天，模型组大鼠直立活动[（0．43±1．13）分]及水平活动得分[（5．86±8．26）分]均低于正常组[分别为（1．75±2．44）分和（13．75±19．02）分]，P〈0．05；海马5-HT含量[（2340±426）ng／g组织]明显低于正常组[（3569±652）ng／g组织]，P〈0．01；中缝核TPH2mRNA相对表达量（0．89±0．15）低于正常组（1．12±0．19），P〈0．05；中缝核TPH2阳性细胞数[（75±29）个]低于正常组[（171±113）个]，P〈0．05。结论孤养加21d应激可造成大鼠抑郁症模型；模型组大鼠海马5-HT含量下降，可能是由于中缝核TPH2的表达减少，使5-HT合成减少所致。Objective To explore changes of the content of 5-hydroxytryptamine （5-HT） in hippocampus and the relative expression of tryptophan hydroxylase 2 （ TPH2 ） in raphe nuclei in rats of depression model. Methods Twenty female Sprague-Dawley rats were randomly divided into two groups （ 10 in each） , normal group and model group, the later was given living alone in combination with 21 day chronic unexpected mild stress （CUMS）. Open-field test was used to evaluate behavioral change, the high performance liquid chromatogram-electrochemical detection, hemi-quantitative reverse transcription - polymerase chain reaction and immunofluorescence were employed to measure 5-HT in hippocampus, to detect the relative expression of TPH2 mRNA and number of TPH2 immunoreactive neurons in raphe nuclei. Results After 21 days of CUMS, both crossing and rearing in model rats were significantly lower than that in control rats in Open-field test. Compared with the control group, hippocampal 5-HT content was decreased in rats of depression model, and so were the relative expression of TPH2 mRNA and number of TPH2 immunoreactive neurons in raphe nuclei. Conclusion Living alone in combination with 21 days of CUMS could induce rats into depression model, the decrease of hippocampal 5-HT content might result from the decrease of TPH2 expression in raphe nuclei, which led to lower the synthesis of 5-HT.

关 键 词：应激 抑郁症 血清素 色氨酸羟化酶 

分 类 号：R686[医药卫生—骨科学]