慢性脑缺血小鼠海马CA1区和视网膜小胶质细胞的动态变化  

Dynamic changes of microglia in hippocampal CA1 and retina of mice with chronic cerebral ischemia

作　　者：付珏秀 赵月阳 贺桂琼[1,2] 骆世芳 Fu Juexiu;Zhao Yueyang;He Guiqiong;Luo Shifang(Center of Neuroscience,Chongqing Medical University,Chongqing 400016,China;Department of Human Anatomy,College of Basic Medicine,Chongqing Medical University,Chongqing 400016,China)

机构地区：[1]重庆医科大学神经科学研究中心,重庆400016 [2]重庆医科大学:基础医学院人体解剖学教研室,重庆400016

出　　处：《神经解剖学杂志》2021年第5期555-561,共7页Chinese Journal of Neuroanatomy

基　　金：成渝地区双城经济圈建设科技创新项目(KJCXZD2020021)。

摘　　要：目的:观察慢性脑缺血(CCI)小鼠海马CA1区和视网膜小胶质细胞(MG)在不同时间点的变化。方法:3月龄C57BL/6J小鼠行改良型双侧颈总动脉结扎(2VO)建立CCI模型,甲苯胺蓝灌注验证模型。建模后7、14和28 d,分别取脑和视网膜进行形态学染色,观察海马CA1区和视网膜的病理改变,以及MG标志物Iba1、M1型指标iNOS、M2型指标TREM2的表达变化。结果:甲苯胺蓝灌注结果显示,2VO术后各组较假手术组小鼠脑组织染色均变浅。HE染色显示,2VO术后7 d海马CA1和视网膜出现细胞水肿,随缺血时间延长细胞排列疏松、异形增多;术后14 d视网膜节细胞层(GCL)细胞数量减少(P<0.001)。免疫组化显示,与假手术组相比,2VO术后各组海马CA1区和视网膜的Iba-1、iNOS阳性细胞数均有不同程度增加(P<0.05)。有趣的是,术后各组海马CA1区TREM2免疫阳性细胞的数量明显减少(P<0.001),而视网膜内TREM2表达增加(P<0.05)。结论:海马和视网膜的MG对脑缺血的反应有一定协同性,视网膜内MG的变化有可能预示脑内炎症变化,但尚需深入研究。Objective:To observe the changes of microglia(MG)in hippocampal CA1 and retina of mice with chronic cerebral ischemia at different time points.Methods:The chronic cerebral ischemia model was established in 3-month-old C57BL/6J mice by modified bilateral common carotid artery ligation(2VO).This model was verified by toluidine blue perfusion staining.7,14,and 28-days after the model was established,histological staining was performed to observe the expression of microglia markers Iba-1,M1 type index iNOS,and M2 type index TREM2 in mice hippocampal CA1 and retina.Results:The results of toluidine blue staining showed that the brain tissue of the mice in each group after 2VO was lighter than that in the sham group.The HE staining showed that there was cellular edema in hippocampal CA1 and retina at 7 days after 2VO.And the cell arrangement became loose and cell abnormalities increased with the prolonged ischemic time.The number of retinal ganglion cell layer(GCL)cells decreased at 14 days after 2VO(P<0.001).Immunohistochemistry showed that compared with the sham group,the number of cells with positive expression of Iba-1 and iNOS in hippocampus CA1 and retina increased to different degrees in each group after 2VO(P<0.05).Interestingly,the expression of TREM2 in the hippocampal CA1 of each group was significantly reduced(P<0.001),while the expression of TREM2 in the retina increased(P<0.05).Conclusion:The MG in hippocampus and retina has a certain synergy in response to chronic cerebral ischemia.The changes of MG in the retina may indicate the inflammatory changes in the brain,but further research is needed.

关 键 词：慢性脑缺血 小胶质细胞 视网膜 海马 小鼠 

分 类 号：R743.3[医药卫生—神经病学与精神病学] R774.1[医药卫生—临床医学]