捕食应激致大鼠持续性情绪唤醒障碍时血浆皮质酮及海马皮质类固醇受体表达变化  

Alterations of plasma corticosterone and hippocampal corticosteroid receptors in rats with the lasting emotionality following predator stress

作　　者：王庆松[1] 王伟文[1] 吴渝宪[1] 林杭[1] 曹仁存[1] 向阳[1] 王俊[1] 

机构地区：[1]成都军区总医院神经内科,610083

出　　处：《中华精神科杂志》2008年第1期49-52,I0003,共5页Chinese Journal of Psychiatry

基　　金：成都军区十五医药卫生科研基金课题资助项目（04A011）

摘　　要：目的探讨严重心理应激所致情感行为异常的相关神经生物学机制。方法将136只雄性Wistar大鼠随机分为捕食应激组（以下简称应激组）和正常对照组（以下简称对照组），每组68只。以放射免疫分析法检测应激后1h、1d、1周，以及1，2，4个月时血浆皮质酮水平，并采用免疫组化和蛋白质免疫印迹法，检测海马糖皮质激素受体（GR）及盐皮质激素受体（MR）表达的变化规律。结果（1）血浆皮质酮水平：应激后1h应激组[（44.5±9．3）μg／L]高于对照组[（22．6±4．0）μg／L，P〈0．01]，但应激后1d降至正常水平，而应激后1周至4个月则明显低于对照组[应激组分别为（μg／L）12．4±2．5，9．8±2．1，8．7±2．1，10．1±2．3，对照组分别为（μg／L）20．8±3．9，21．1±4．2，16．6±3．6及20．2±4．0；P〈0．01]。（2）海马GR和MR阳性免疫反应信号：应激后1d免疫组化研究显示，应激大鼠海马及额叶皮层GR均较对照组增强（P〈0．01），其中以海马结构的改变更明显（P〈0．05）；而MR则显著降低（P〈0．01）。海马免疫印迹检测进一步揭示，应激组海马GR表达于应激后1d至4个月明显增高（P〈0．05），而MR表达则于应激后1h至1个月显著低于对照组（P〈0．05）。结论捕食应激后大鼠出现血浆皮质酮双向变化、海马GR和MR失衡以及不同的变化规律，这种严重的心理应激在引发大鼠持续性情绪唤醒障碍中可能有重要作用。Objective To explore the neurobiologieal basis involved in the pathogenesis of the lasting emotionality following severe psychological stress. Methods Mtogether 136 male Wistar rats were randomly divided into two groups, and the predator stress group （ n = 68 ） was for non-injurious exposure of eats until slightly frightened twitch and nares flaring due to polypnea for 6 min, and normal control group （n =68）. The plasma concentrations of eortieosterone and expressions of glueoeortieoid （GR） and mineraloeortieoid receptors （ MR ） in hippoeampus were investigated by radioimmunoassay, immunohistoehemistry and the Western blot analyses. Results The plasma eortieosterone concentration in stress rats was significantly increased at 1 h after predator stress compared with the controls [ （44. 5 ±9.3） vs. （22. 6 ±4. 0） μg/L, P 〈0. 01 ] , then declined to the normal level on 1 d after eat exposure. However, the stress rats showed a lasting significant reduction in plasma eortieosterone levels from 1 week to 4 months （μg/L） 12. 4 ±2. 5, 9.8 ±2.1, 8.7 ±2.1 and 10. 1 ±2. 3 in stress rats vs. （μg/L） 20. 8 ±3.9, 21. 1± 4. 2, 16. 6 ± 3.6 and 20. 2 ± 4.0 in controls （ P 〈 0.01 ）. The immunohistoehemistry analyses revealed that the GR-immunoreaetivity in brain tissue of stress rat was significantly increased than controls at 1 d after eat exposure （P 〈 0. 01 ）, and even more higher in hippoeampus （P 〈 0. 05 ）, while the MR-immunoreaetivity was remarkably decreased than the eontrols （P 〈0. 01 ）. Meanwhile, the Western analyses revealed further that the expression of hippoeampal GR in stress rats increased remarkably from 1 d to 4 months after predator stress compared with the controls （ P 〈 0. 05 ）, whereas that of MR was significantly reduced from 1 h to 1 month after predation （P 〈 0. 05 ）. Conclusion The biphasie and lasting alterations of plasma corticosterone and the disbalance of hippocampal GR/MR expressions involved in the neuronal hyperexcita

关 键 词：应激 海马 皮质酮 受体 糖皮质激素 受体 盐皮质激素 

分 类 号：R686[医药卫生—骨科学]