Development
The development of the long astrocyte cellular processes that are integral to the glia limitans structure has been linked to the presence of meningeal cells in the pia mater. Meningeal cells are specialized fibroblast-like cells that surround the CNS and major blood vessels. They have been found to co-operate with astrocytes in the initial formation of the glia limitans during development and participate in its continued maintenance throughout life. Artificially induced destruction of meningeal cells during CNS development have been found to result in the alteration of subpial extracellular matrix and a disruption of the glia limitans.
The glia limitans has also proven to be important in the recovery of the CNS after injuries. When lesions are made on the brain surface, meningeal cells will divide and migrate into the lesion, eventually lining the entire injury cavity. If the injury has significantly reduced the density of astrocytes and created space within the tissue, the meningeal cells will invade even more diffusely. As invading meningeal cells make contact with astrocytes, they can induce the formation of a new, functional glia limitans. The new glia limitans formed after CNS injury usually presents itself as a barrier to regenerating axons.
Read more about this topic: Glia Limitans
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