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The layer of epithelial cells lining the cavities of the brain and spinal cord. Also known as ependymal layer.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



cells in the brain of animals and man that perform demarcating, supportive, and secretory functions in the central nervous system; a form of neuroglia.

The ependyma separates from cells of the neural tube in early embryogenesis. Ependymal cells (ependymocytes) line the walls of the spinal canal and ventricles of the brain. They have elongated bodies with cilia at the free end. The cilia, which are lost in many parts of the brain after the individual is born, help the cerebrospinal fluid to circulate by their beating movements. A long, branched process extends from the opposite end of the ependymocyte into the brain. The ependyma of the walls of the third ventricle may promote the exchange of biologically active substances between neurons of the adjacent regions of the brain, cerebrospinal fluid, and blood vessels of the hypophyseoportal system.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Aquaporin4 knockout mice develop marked hydrocephalus, probably because of reduced water clearance through the ependyma and brain-blood barrier.
Guerra et al., "Astrocytes acquire morphological and functional characteristics of ependymal cells following disruption of ependyma in hydrocephalus," Acta Neuropathologica, vol.
The structure of the cerebral ventricles is subjected to significant changes which enclose marked polymorphism of ependyma cells, disturbances of their continuity of their layer at considerable length.
The CSF-lymphatic link into nasal submucosa effects the ependyma and provides a regulatory mechanism which helps to balance the repetitive production and re-absorption of CSF (15).
Intermediate filament proteins in choroid plexus and ependyma and their tumors.
Unfortunately, the ependyma may be destroyed by significant dilatation of the central canal.
A few studies, however, indicated for an alternative pathway of virus entry following direct intbction of microvascular endothelial cells of the blood brain barrier (31), Following entry the second step is getting past the glia limitans (layer formed due to astrocytic end foot interdigitating with piamater along the surface and ependyma along the ventricles) which is an additional barrier both functionally and structurally.
Medially the MD is lined with 3rd ventricular ependyma lying immediately adjacent to the 3rd ventricle, except where the paraventricular nucleus is interposed.
Ependymomas originate from the ependyma cells, which are lining the spinal cord's central canal.10 "These cells vary from cuboidal to flat and modulate the transfer of fluid between the cerebrospinal fluid (CSF) and the cells of the nervous system".
They were located near the soft cerebral membrane, chiefly in the regions of the posterior long fasciculi, the nuclei of the abducent vestibular and trigeminus nerves, under the ependyma, in the area of the cochlear nerve nuclei, the Gover's fasciculi, and in the base of the cerebellum.