Ependymal cells (or épendymocytes) are cousins astrocytes. They provide the coating
ventricles of the CNS and thus play a role in exchanges between the CNS and cerebrospinal fluid (CSF)
contained in these cavities.
The ependymal cells in the ventricles are loosely joined together by special intercellular adhesion sites called desmosomes, which enable the cells to form a nearly continuous epithelial sheet over the surface of the ventricles and spinal canal. Because the junctions between the ependymal cells are loose, CSF is able to diffuse from the ventricles into the central nervous system. The cells surrounding the choroid plexus are connected by tight junctions, which prevent the leakage of substances and fluids from the blood vessels into the CSF. This protects against the unregulated entry of potentially harmful substances into the ventricles and ultimately the central nervous system.
ventricles of the CNS and thus play a role in exchanges between the CNS and cerebrospinal fluid (CSF)
contained in these cavities.
The ependymal cells in the ventricles are loosely joined together by special intercellular adhesion sites called desmosomes, which enable the cells to form a nearly continuous epithelial sheet over the surface of the ventricles and spinal canal. Because the junctions between the ependymal cells are loose, CSF is able to diffuse from the ventricles into the central nervous system. The cells surrounding the choroid plexus are connected by tight junctions, which prevent the leakage of substances and fluids from the blood vessels into the CSF. This protects against the unregulated entry of potentially harmful substances into the ventricles and ultimately the central nervous system.
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