Ultrastructural observations of astrocyte end-feet in the rat central nervous system

作     者：Nakazawa, E Ishikawa, H 

作者机构：Gunma Univ Sch Med Dept Anat Maebashi Gumma 3718511 Japan 

出 版 物：《JOURNAL OF NEUROCYTOLOGY》 (脑细胞生物学杂志)

年 卷 期：1998年第27卷第6期

页      面：431-440页

核心收录：

学科分类：0710[理学-生物学] 1001[医学-基础医学(可授医学、理学学位)] 07[理学] 071003[理学-生理学] 

基　　金：Ministry of Education  MOE 

主　　题：星形细胞/代谢 星形细胞/超微结构 脑/代谢 脑/超微结构 细胞膜/超微结构 中枢神经系统/代谢 中枢神经系统/超微结构 小脑/代谢 小脑/超微结构 细胞骨架/超微结构 神经胶质原纤维酸性蛋白质/代谢 免疫印迹法 中间丝蛋白质类/代谢 中间丝/超微结构 显微镜检查 荧光 显微镜检查 免疫电子 微管/超微结构 视神经/代谢 视神经/超微结构 网蛋白质 大鼠 Wistar 动物 大鼠 

摘      要：Astrocytic end-feet in the rat CNS were studied by thin-section electron microscopy. Astrocyte processes that enclose neuronal elements extended to blood vessels and the pia mater, where the processes expanded to form end-feet or glial limiting membranes. At the end-feet, cell junctions such as gap junctions and desmosome-like junctions were formed between the astrocyte processes. The end-foot plasma membrane facing the basal lamina was undercoated with electron-dense, layered materials, with an internal substructure of filamentous networks, with which bundles of glial filaments (GFs) appeared to be closely associated via fine filamentous structures, often showing a hemi-desmosome-like appearance. In specimens treated with Triton X-100. the internal substructure of the undercoat was better visualized and the association with GFs was well preserved. At the end-feet, some unique tubular structures were found in spatial relationship to the plasmalemmal undercoat. Plectin visualized by immunofluorescence was localized to astrocytes and their processes, especially at the end-feet facing the pia mater. Immunoelectron microscopy located plectin on fine filamentous structures lying between GFs and the plasmalemmal undercoat. These observations suggest that plasmalemmal undercoats at the astrocyte end-feet may serve as attachment sites of GFs to the plasma membrane and that plectin may be involved in such attachment.