缰核损毁对大鼠认知功能影响的研究

发布时间：2018-09-01 16:27

【摘要】：缰核（Habenula nucleus, Hb）是前脑边缘系统与中脑和脑干联系的重要枢纽，通过复杂的纤维联系与神经递质参与中枢神经系统多种功能活动。最近发现Hb在认知过程中起着重要作用，但其机制尚未明确。目的：本研究拟通过损毁Hb观察大鼠脑内DA系统和Ach系统的微量变化，以期探究Hb影响认知功能的可能作用途径和机制，从而为临床上各种认知功能损害性疾病提供新的诊断和治疗依据。方法: 实验分为三组，即正常对照组、假手术组和Hb毁损组。应用Morris水迷宫测验观察Hb损毁大鼠的行为学变化；应用ELISA免疫法观察Hb损毁大鼠脑脊液及海马中乙酰胆碱酯酶（AchE）含量的变化以及脑脊液和黑质中多巴胺（DA）含量的变化；应用免疫组织化学染色的方法研究Hb损毁大鼠炓质中酪氨酸氢化酶（TH）及海马中胆碱乙酰转移酶（ChAT）表达的变化。结果：本实验结果显示：（1）行为学测试结果：在定位航行实验中，假手术组大鼠与正常组大鼠比较无明显差异（P0.05），Hb损毁组大鼠逃避潜伏期延长，，与假手术组及正常组均有极显著差异（P0.01）；在空间探索实验中，假手术组大鼠在100秒内到达平台的次数与正常组大鼠无明显差异（P0.05）；Hb损毁组大鼠较假手术组及正常对照组明显减少（P0.01）。（2）AchE和DA含量的变化：Hb损毁后脑脊液AchE含量明显减少（P0.01），但是海马AchE含量无明显变化（P0.05）；Hb损毁后黑质DAChAT和TH阳性细胞数的变化：Hb损毁组大鼠海马ChAT阳性细胞数无明显变化（P0.05）；黑质TH阳性细胞数目显著增多（P0.01）。结论：本实验结果证实：（1）损毁Hb后的大鼠空间记忆和探索等学习能力明显降低，说明Hb参与神经系统认知功能过程的调节。（2）Hb损毁后，脑脊液AchE含量减少，海马AchE及ChAT含量未见明显变化，提示Hb参与脑中Ach的释放，但是不影响海马Ach的含量。（3）Hb损毁后，黑质中DA含量增多，TH含量增多，提示Hb参与黑质中DA的释放和传递。
[Abstract]:Habenula nucleus (Hb) is an important junction between the forebrain limbic system and the middle brain and brain stem. It participates in many functional activities of the central nervous system through complex fiber connections and neurotransmitters.
Objective:
The purpose of this study is to observe the changes of DA and Ach systems in rat brain by destroying Hb, so as to explore the possible pathway and mechanism of Hb affecting cognitive function, and to provide a new basis for clinical diagnosis and treatment of various cognitive impairment diseases.
Method:
The experiment was divided into three groups: normal control group, sham operation group and Hb lesion group. Immunohistochemical staining was used to study the changes of tyrosine hydrogenase (TH) and choline acetyltransferase (ChAT) expression in the hippocampus of rats with Hb lesion.
Result:
The results showed that: (1) Behavioral test: in the positioning navigation experiment, there was no significant difference between the sham-operated group and the normal group (P 0.05), the escape latency of rats in the Hb lesion group was prolonged, which was significantly different from the sham-operated group and the normal group (P 0.01); in the space exploration experiment, the sham-operated group rats arrived within 100 seconds. There was no significant difference between the number of platforms and normal rats (P 0.05); the number of DAChAT and TH positive cells in substantia nigra after Hb lesion decreased significantly (P 0.01). Changes: The number of ChAT positive cells in hippocampus of rats with Hb lesion did not change significantly (P 0.05), and the number of TH positive cells in substantia nigra increased significantly (P 0.01).
Conclusion:
The results showed that: (1) the spatial memory and exploratory learning ability of rats with Hb lesion were significantly decreased, indicating that Hb participated in the regulation of cognitive function of the nervous system. (2) After Hb lesion, the content of AchE in cerebrospinal fluid decreased, while the contents of AchE and ChAT in hippocampus did not change significantly, suggesting that Hb participated in the release of Ach in the brain, but did not affect the content of Ach in hippocampus. (3) after Hb damage, DA content in substantia nigra increased and TH content increased, suggesting that Hb was involved in the release and transmission of DA in substantia nigra.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R749.1

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