舍曲林对抑郁模型大鼠海马区细胞结构与PSD-95表达水平的影响

发布时间：2018-05-16 18:59

本文选题：抑郁症 + 海马　；参考：《新乡医学院》2013年硕士论文

【摘要】：背景抑郁症是一种以心境低落为主要特征的慢性反复发作性疾病,严重影响着全球约20%人群的身心健康以及生活质量。目前抑郁症的发生机制尚不明确。近年来,海马神经可塑性的研究成为抑郁症发病机制研究的热点之一。同时,突触后致密蛋白-95(postsynaptic density protein-95, PSD-95)是位于突触后特化区内的主要支架蛋白,在调控神经突触发育和可塑性中起关键作用,并参与学习记忆等功能的调节。课题拟通过研究抑郁模型大鼠海马区PSD-95的表达和神经元细胞结构在药物干预下的改变,从而探讨抑郁症可能的发病机制。目的 1.探讨抑郁模型大鼠学习记忆能力变化及药物干预的影响。 2.探讨抑郁模型大鼠海马神经元形态变化以及药物干预的改变。 3.探讨抑郁模型大鼠海马各区PSD-95表达水平及药物干预对其影响。 4.探讨抑郁模型大鼠海马各区PSD-95蛋白表达水平与学习记忆能力之间的关系。方法 1.大鼠先分为正常对照组(n=16)和造模组(n=48)。造模组建立慢性不可预见应激(chronic unpredictable stress, CUS)抑郁模型,再将造模组分为三组：抑郁模型组(n=16,不进行灌胃操作)、生理盐水组(n=16,每日灌胃注入生理盐水)和药物干预组(n=16,每日灌胃注入舍曲林)。 2.通过测量体重、蔗糖水消耗试验和旷场试验检测大鼠的行为学变化,通过Y迷宫检测大鼠的学习记忆等认知功能。 3.采用HE染色法观察大鼠海马区神经元锥体、颗粒细胞形态结构。 4.采用免疫组化方法检测四组大鼠海马区PSD-95蛋白表达水平；运用逆转录聚合酶链反应(RT-PCR)法检测海马区PSD-95mRNA的表达水平。 5.采用相关分析法分析药物干预后四组大鼠海马各区PSD-95蛋白表达水平与学习记忆能力之间的关系。结果 1.造模前后及药物干预后结果：大鼠造模前在体重(t=1.967,P0.05)、蔗糖水消耗(t=1.352,P0.05)、旷场试验中央停留时间(t=0.073,P0.05),水平运动距离(t=-0.184,P0.05)、竖立次数(t=-0.396,P0.05),Y迷宫试验错误反应次数(t=-0.404,P0.05),正确反应次数(t=-0.805,P0.05),总潜伏期时间(t=-0.455,P0.05)差异均无统计学意义,提示可进行CUS模型建立。造模后在体重(t=18.909,P0.05)、蔗糖水消耗(t=-20.414,P0.05)、旷场试验中央停留时间(t=-10.420,P0.05)、水平运动距离(t=-11.859,P0.05)、竖立次数(t=14.060,P0.05),Y迷宫试验错误反应次数(t=--6.140,P0.05),正确反应次数(t=8.28,P0.05),总潜伏期时间(t=-17.66,P0.05)差异有统计学意义,证明抑郁模型建立成功。药物干预结束后,四组大鼠行为学评分比较：体重(F=454.279,P0.05),蔗糖水消耗(F=172.896,P0.05),旷场试验中央停留时间(F=246.178,P0.05),水平运动距离(F=430.354,P0.05),竖立次数(F=1354.272,P0.05),Y迷宫试验错误反应次数(F=23.150,P0.05),正确反应次数(F=40.258,P0.05),总潜伏期时间(F=129.083,P0.05)差异均具有统计学意义,显示抑郁模型大鼠各项行为学指标降低且空间学习、记忆提取与保持能力下降,药物干预可改善抑郁状态以及学习记忆能力。 2.HE染色结果：抑郁模型大鼠海马区神经元细胞形态结构发生病理性改变；通过药物干预可使其改善。四组大鼠海马区神经元锥体、颗粒细胞数目(FCA1=8.228,P0.05；FCA3=34.143,P0.05；FDG=275.035,P0.05),神经元锥体、颗粒细胞灰度值(FCA1=88.494,P0.05；FCA3=89.398,P0.05；FDG=236.085,P0.05),差异有统计学意义。 3.免疫组化结果：四组大鼠海马区PSD-95蛋白阳性细胞数目(FCA1=16.497,P0.05；FCA3=23.494,P0.01；FDG=37.628,P0.05),阳性细胞积分光密度(FCA1=26.659,P0.05；FCA3=13.556,P0.05；FDG=6.158,P0.05),差异有统计学意义,显示PSD-95表达水平不同。 4. RT-PCR结果：四组大鼠海马区PSD-95mRNA表达情况比较(F=290.951,P0.05),其中抑郁模型大鼠表达水平低于正常组(P0.05),药物干预组大鼠表达水平高于抑郁模型大鼠(P0.05),差异具有统计学意义。其余各组比较差异无统计学意义。 5. Pearson相关性分析结果：四组大鼠海马CA1区、CA3区和DG区PSD-95阳性细胞数目与Y迷宫各参数相关性分析,其中抑郁模型大鼠海马CA1区PSD-95阳性细胞数目与错误反应次数呈负相关(r=-0.769,P0.05)、与总逃避潜伏期呈负相关(r=0.800,P0.05)、与正确反应次数呈正相关(r=0.800,P0.05),抑郁模型大鼠海马CA3区PSD-95阳性细胞数目与错误反应次数呈负相关(r=-0.751,P0.05)、与总逃避潜伏期呈负相关(r=-0.832,P0.05)、与正确反应次数呈正相关(r=0.862,P0.05),抑郁模型大鼠海马DG区PSD-95阳性细胞数目与错误反应次数呈负相关(r=-0.699,P0.05)、与总逃避潜伏期时间呈负相关(r=-0.869,P0.05)、与正确反应次数呈正相关(r=0.728,P0.05)。结论 1.抑郁症中海马神经可塑性参与情绪、学习记忆功能的调节,海马神经元细胞形态结构及数量的改变可能是神经可塑性及抑郁症发生的形态学基础。 2.舍曲林能改善抑郁模型大鼠的学习记忆认知功能并逆转海马内PSD-95低表达以及神经元细胞形态结构病理可塑性改变,可能是舍曲林抗抑郁机制作用之一。
[Abstract]:background
Depression is a chronic and recurrent disease characterized by depression, which seriously affects the physical and mental health and quality of life of about 20% people around the world. The mechanism of depression is not yet clear. In recent years, the study of hippocampal plasticity has become one of the hotspots in the study of the pathogenesis of depression. -95 (postsynaptic density protein-95, PSD-95) is the main scaffold protein in the postsynaptic special area. It plays a key role in regulating the development and plasticity of synapse, and participates in the regulation of learning and memory. The topic is to study the expression of PSD-95 in the hippocampus of the depressive model rats and the neuron cell structure in the drug. Interventions to explore possible mechanisms of depression.
objective
1. to explore the changes of learning and memory ability and the effect of drug intervention in depression model rats.
2. to explore the morphological changes of hippocampal neurons in rats with depression and the changes of drug intervention.
3. to investigate the expression level of PSD-95 in hippocampus of depression model rats and the effect of drug intervention.
4. to explore the relationship between PSD-95 protein expression and learning and memory ability in hippocampus of depression model rats.
Method
The 1. rats were first divided into normal control group (n=16) and model group (n=48). The model of chronic unforeseeable stress (chronic unpredictable stress, CUS) depression model was established, and then the model group was divided into three groups: depression model group (n=16, no gastric perfusion), saline group (n=16, daily intragastric injection of saline) and drug intervention group (n=16, each) Daily intragastric injection of sertraline.
2. by measuring body weight, sucrose water consumption test and open field test, the behavioral changes of rats were detected, and the learning and memory functions of rats were detected by Y maze.
3. HE staining was used to observe the pyramidal structure and granule cell morphology of hippocampal neurons in rats.
4. the expression level of PSD-95 protein in the hippocampus of four rats was detected by immunohistochemical method, and the expression level of PSD-95mRNA in the hippocampus was detected by reverse transcription polymerase chain reaction (RT-PCR).
5. correlation analysis was used to analyze the relationship between PSD-95 protein expression and learning and memory ability in four groups of hippocampus after drug intervention.
Result
1. before and after modeling and after the drug intervention: the body weight (t=1.967, P0.05), sucrose water consumption (t=1.352, P0.05), t=0.073 (P0.05), t=-0.184, P0.05, t=-0.396, P0.05, Y labyrinth test. 0.05) the total latency time (t=-0.455, P0.05) was not statistically significant, suggesting that CUS model could be established.
After the model, the body weight (t=18.909, P0.05), the sucrose water consumption (t=-20.414, P0.05), the central residence time (t=-10.420, P0.05) in the open field test, the horizontal movement distance (t=-11.859, P0.05), the vertical number of times (t=14.060, P0.05), the false reaction times of Y labyrinth test, the correct response times, the total latency time. The difference was statistically significant, demonstrating the success of the depression model.
After the drug intervention, the four groups of rats' behavioral score were compared: weight (F=454.279, P0.05), sucrose water consumption (F=172.896, P0.05), central stay time (F=246.178, P0.05) in open field test, horizontal movement distance (F=430.354, P0.05), vertical frequency (F= 1354.272, P0.05), Y labyrinth test error times (F=23.150, P0.05), and the correct response times 40.258, P0.05), the difference in total latency time (F=129.083, P0.05) was statistically significant, which showed that the behavioral indexes of the depression model rats were reduced and the spatial learning, the ability of memory extraction and retention decreased, and the drug intervention could improve the state of depression and the learning and memory ability.
2.HE staining results: the morphological and structural changes of neurons in the hippocampus of the depression model rats were histopathologically altered. The pyramids of the neurons in the hippocampus of the four groups of rats, the number of granular cells (FCA1=8.228, P0.05; FCA3=34.143, P0.05; FDG=275.035, P0.05), the pyramids of the neurons, the gray value of granular cells (FCA1=88.494, P0.0) 5; FCA3=89.398, P0.05; FDG=236.085, P0.05), the difference was statistically significant.
3. the results of immunohistochemistry: the number of PSD-95 protein positive cells in the hippocampus of four rats (FCA1=16.497, P0.05; FCA3=23.494, P0.01; FDG=37.628, P0.05), the integral light density of positive cells (FCA1=26.659, P0.05; FCA3=13.556, P0.05; FDG=6.158,), which showed that the expression level was different.
4. RT-PCR results: the expression of PSD-95mRNA in the hippocampus of the four rats was compared (F=290.951, P0.05), in which the expression level of the depression model rats was lower than that of the normal group (P0.05). The expression level of the rats in the drug intervention group was higher than that of the depression model rats (P0.05), the difference was statistically significant. The other groups had no statistical significance.
5. Pearson correlation analysis: the correlation between the number of PSD-95 positive cells in the hippocampal CA1, CA3 and DG areas in the hippocampus of the four rats was correlated with the parameters of the Y maze, in which the number of PSD-95 positive cells in the hippocampus CA1 region was negatively correlated with the number of false reactions (r=-0.769, P0.05), and was negatively correlated with the total escape latency (r=0.800, P0.05), and positive. The number of positive responses was positively correlated (r=0.800, P0.05). The number of PSD-95 positive cells in the hippocampus CA3 area of the depression model rats was negatively correlated with the number of wrong responses (r=-0.751, P0.05), which was negatively correlated with the total escape latency (r=-0.832, P0.05), and was positively correlated with the number of correct responses (r=0.862, P0.05), and the number of PSD-95 positive cells in the hippocampus DG region of the depressive model rats. There was a negative correlation with the number of errors (r=-0.699, P0.05), which was negatively correlated with the total escape latency time (r=-0.869, P0.05), and had a positive correlation with the number of correct responses (r=0.728, P0.05).
conclusion
1. the plasticity of hippocampus nerve plasticity participates in emotion, learning and memory function is regulated, the morphological structure and quantity of hippocampal neurons may be the morphological basis of nerve plasticity and depression.
2. sertraline can improve the cognitive function of learning and memory in the depression model rats and reverse the low expression of PSD-95 in the hippocampus and the morphological and pathological changes in the morphological structure of neurons. It may be one of the antidepressant mechanisms of sertraline.

【学位授予单位】：新乡医学院
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R749.4;R-332

【参考文献】