摘要
目的运用无偏体视学方法定量研究慢性不可预知应激(chronic unpredictable stress,CUS)模型大鼠海马DG体积、DG突触密度、突触总数的改变情况。方法筛选4~5周龄雄性SD大鼠分为对照组(n=15)和CUS组(n=23)。CUS组大鼠通过孤养并结合慢性不可预知应激方式建立模型,对照组每5只为1笼,正常喂养。建模期间,每周进行糖水偏好试验。建模4周后,结合糖水偏好试验、旷场实验、高架十字迷宫实验对两组大鼠行为学表现进行评估。随后运用现代体视学与免疫组织化学相结合的方法测量两组大鼠海马DG体积、DG突触密度和突触总数。结果经过4周CUS干预后,CUS组大鼠与对照组相比,体质量显著降低(P<0.05),糖水偏好显著下降(P<0.05);旷场实验中央区域路程、中央路程比和中央时间比显著降低(P<0.05)。CUS组大鼠海马DG突触密度[(0.48±0.13)/μm^3]和突触总数(6.713 5×10~8)较对照组大鼠[突触密度(0.15±0.03)/μm^3,突触总数(2.103 3×10~9)]显著下降(P<0.05)。结论抑郁症模型大鼠海马DG的突触总数减少、突触密度减小,表明海马齿状回突触改变可能是抑郁症发病的重要神经结构基础之一。
Objective To investigate the changes of dentate gyrus volume, and density and number of spinal synapses from the depressed rats induced by chronic unpredictable stress （CUS） by unbiased stereology. Methods Male Sprague-Dawley （SD） rats （4- to 5-week-old ） were randomly divided into control group （ n = 15 ） and CUS group （ n = 23 ）. The rats from the CUS group were housed in single and given CUS including cold/warm water, food/water deprivation in order to build a depressed model. The animals of the control group were housed in 5 and given ad libitum access to food and water. During the 4 weeks of modeling, the rats of the both groups were evaluated using the sucrose preference test, open field test and elevated plus maze test for the behavior assessment. Then the total volume of DG, and numerical density and total number of spinal synapses in DG were studied with immunohistochemical assay and stereology. Results The body mass and percentage of sucrose preference were significantly decreased in the CUS group than the control group （ both P 〈 0.05 ）. In the open field test, the total time spent in the inner area and total traveled distance of 5 min in the inner area were significantly lower in the CUS group than control group （P 〈0.05 ）. According to the stereological results, the numerical density and total number of spinal synapses in DG were significantly decreased in the CUS group when compared to the control group （0.48 ±0.13/μm^3 vs 0. 15 ±0.03μm^3, 2. 103 3 × 10^9 vs 6. 713 5 × 10^8, P 〈0.05）. Conclusion The synapse loss in the hippocampal DG area in the CUS-induced depressed rats might be one of the important neurological structure bases for pathogenesis of depression.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2016年第13期1506-1511,共6页
Journal of Third Military Medical University
基金
国家自然科学基金面上项目(81470057)
国家自然科学基金青年科学基金(31300985,81171238,)
重庆市首批“百名学术学科领军人才”培养计划(渝教人[2012]44号)
关键词
抑郁症大鼠
海马
齿状回
突触
体视学
depressed rats
hippocampus
dentate gyrus
synapse
stereology
