小鼠视神经轴索损伤后轴突与小胶质细胞变化的初步研究

发布时间：2018-04-05 04:40

本文选题：YFP小鼠　切入点：GFP小鼠　出处：《兰州大学》2017年硕士论文

【摘要】：中枢神经系统疾病的治疗和功能的恢复一直是医学界的难题。眼内存在的创伤应激、病理机制、炎症反应等与脑和脊神经中十分相似,是中枢神经系统研究的重要模型。目前对小胶质细胞在中枢神经创伤和疾病中的作用还不能定论。本实验以视神经轴突被标记的THY1-YFP H-lin转基因小鼠和小胶质细胞被标记的GFP-C57BL/6转基因小鼠为实验对象,建立成体小鼠单侧眼视神经轴索钝性损伤模型,在手术后4小时、1天、3天、5天、10天分离视神经,用共聚焦荧光显微镜观察视神经轴突退行性病变和小胶质细胞的变化。实验结果显示,视神经损伤后退行性病变可分为三个阶段,一是起始阶段:损伤后4小时,视神经损伤处轴突呈断开状态,形成胶质瘢痕,静息态小胶质细胞大量出现,其中部分激活并向受损区迁移。二是退行性病变阶段:损伤后1~5天,视神经轴突从部分念珠化到大量念珠化,说明神经轴突已经进入退行性病变进程,可以观察到激活态小胶质细胞大量增多并覆盖损伤区。三是退行性病变快速恶化阶段:损伤后5、10天,视神经轴突的退行性病变持续恶化,轴突从念珠状转变为碎片状,激活态小胶质细胞聚集且数量保持稳定,少数小胶质细胞有向静息态转变的趋势。实验中也发现小鼠单侧眼损伤后,其对侧眼中也出现了大量的小胶质细胞,这些细胞虽然被激活但并没有对正常的神经轴突产生影响。本实验的结果表明成体小鼠视神经损伤后轴突的退行性病变持续恶化并伴随着小胶质细胞的激活和增多,说明小胶质细胞与视神经的退行性病变密切关联。本实验旨在通过视神经损伤模型了解中枢神经退行性病变和小胶质细胞的作用,为这类疾病的研究提供新的思路。
[Abstract]:The treatment and recovery of central nervous system diseases has been a difficult problem in the medical field.Traumatic stress, pathological mechanism and inflammatory reaction in the eye are very similar to those in the brain and spinal nerve, and are important models for the study of the central nervous system (CNS).The role of microglia in central nervous trauma and disease is uncertain.In this experiment, THY1-YFP H-lin transgenic mice labeled with optic nerve axons and GFP-C57BL/6 transgenic mice labeled with microglia were used as experimental objects to establish the model of unilateral optic nerve axonal blunt injury in adult mice.The optic nerve was separated from the optic nerve 4 hours a day, 3 days, 5 days and 10 days after operation. The changes of axonal degeneration and microglia of optic nerve were observed by confocal fluorescence microscope.The experimental results show that the degenerative lesions after optic nerve injury can be divided into three stages. One is the initial stage: 4 hours after the injury, the axons of the optic nerve are disconnected, the glial scar is formed, and the resting microglia appear in large numbers.Some of them were activated and migrated to the damaged area.Second, degenerative lesion stage: the axons of optic nerve changed from partial rosary to large amount of rosary on the 1st and 5th day after injury, which indicated that the axons of the nerve had entered the process of degenerative lesion, and the active microglia could be observed to increase a lot and cover the injured area.The third is the stage of rapid deterioration of degenerative lesions: after 5 to 10 days of injury, the degeneration of optic nerve axons continued to deteriorate, the axons changed from beads to fragments, the activated microglia gathered and the number of activated microglia remained stable.A small number of microglial cells have a tendency to move to a resting state.It was also found that a large number of microglia appeared in the contralateral eyes after unilateral eye injury. Although these cells were activated, they did not affect the normal axons.The results of this study showed that the axonal degeneration of adult mice after optic nerve injury continued to deteriorate with the activation and increase of microglia indicating that microglia were closely related to optic nerve degenerative lesions.The purpose of this study was to understand the role of neurodegenerative lesions and microglia in central nervous system by optic nerve injury model, and to provide new ideas for the study of these diseases.
【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R741

【相似文献】