X-Irradiation for Promoting Recovery in Lesioned Adult Mammalian CNS
The role of the non-neuronal cells, the glial cells and, in particular, the reactive astrocytes in the failure of the severed adult CNS axons to regrow beyond the lesion site has been a topic of many studies and of much debate for almost a century (e.g., Reier et al., 1989). The current consensus is that the glia have a pivotal role in control of the fate of axonal regeneration. However, there are several points of ongoing debate; for one, the identity of the subset of the glial cell populations which plays the key role is yet to be resolved. In addition, it is not clear whether adult CNS glia inhibit or enhance axonal regeneration and whether their effects are directly exerted on the axons or mediated via a cascade of cellular interactions. In spite of the extensive research, to date, it is not known which cell types and which environment the severed axons encounter after injury and whether the physical encounter with a certain cell type plays any role in determining the fate of axonal regeneration in situ.
KeywordsOlfactory Bulb Reactive Astrocyte Axonal Regeneration Glial Scar Mitral Cell
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