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Radial glial cells are bipolar-shaped cells that span the width of the cortex in the developing central nervous system (CNS) and serve as primary progenitors capable of generating neurons, astrocytes, and oligodendrocytes. During development, newborn neurons use radial glia as scaffolds, traveling along the radial glial fibers in order to reach their final destinations. Despite the various possible fates of the radial glial population, it has been demonstrated through clonal analysis that most radial glia have restricted, unipotent or multipotent, fates. Radial glia can be found during the neurogenic phase in all vertebrates (studied to date). The term "radial glia" refers to the morphological characteristics of these cells that were first observed: namely, their radial processes and their similarity to astrocytes, another member of the glial cell family. ==Discovery== Camillo Golgi, using his silver staining technique (later deemed the Golgi method), first described radially oriented cells spanning from the central canal to the outer surface of the embryonic chick spinal cord, in 1885. Using the Golgi method, Giuseppe Magini then studied the mammalian fetal cerebral cortex in 1888, confirming the similar presence of elongated radial cells in the cortex (also described by Kölliker just before him), and observing “various varicosities or swellings” on the radial fibers. Intrigued, Magini also observed that the size and number of these varicosities increased later in development, and were absent in the adult nervous system. Based on these findings, Magini then hypothesized that these varicosities could be developing neurons. Using a combination Golgi and hematoxylin staining method, Magini was able to identify these varicosities as cells, some of which were very closely associated with the radial fibers.〔 Additional early works that were important in elucidating the identity and function of radial glia, were completed by Ramón y Cajal, who first suggested that the radial cells were a type of glia through their similarities to astrocytes;〔 and Wilhelm His, who also proposed the idea that growing axons may use radial cells for orientation and guidance during development.〔 Despite the initial period of interest in radial glia, little addition information was learned about these cells until the electron microscope and immunohistochemistry became available some 60 years later.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Radial glial cell」の詳細全文を読む スポンサード リンク
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