from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A thin epithelial membrane lining the ventricular system of the brain and the spinal cord
from the GNU version of the Collaborative International Dictionary of English
- n. The epithelial lining of the ventricles of the brain and the canal of the spinal cord; endyma; ependymis.
from The Century Dictionary and Cyclopedia
- n. The lining membrane of the cerebral ventricles (except the fifth) and of the central canal of the spinal cord. Also endyma.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. thin epithelial membrane lining the ventricles of the brain and the spinal cord canal
Langub, MC, et al. Estrogen receptor immunoreactive glia, endothelia and ependyma in guinea pig preoptic area and median eminence: electron microscopy.
It is covered by a thin layer of gray substance continuous with that of the medulla spinalis; superficial to this is a thin lamina of neuroglia which constitutes the ependyma of the ventricle and supports a layer of ciliated epithelium.
On section it is seen that the funiculus separans is formed by a strip of thickened ependyma, and the area postrema by loose, highly vascular, neuroglial tissue containing nerve cells of moderate size.
Above the pons these ascending fibers come to the surface at the side of the reticular formation in the trigonum lemnisci and are covered by a layer of ependyma.
The cerebrospinal fluid, 129 for the most part elaborated by the choroid plexuses, is poured into the cerebral ventricles which are lined by smooth ependyma.
Likewise an ascending current of fluid apparently occurs in the central canal of the spinal cord; this, representing a possible product of the ependyma, may be added to the intraventricular supply.
The ependymal layer is ultimately converted into the ependyma of the central canal; the processes of its cells pass outward toward the periphery of the medulla spinalis.
They are lined by a thin, diaphanous membrane, the ependyma, covered by ciliated epithelium, and contain cerebrospinal fluid, which, even in health, may be secreted in considerable amount.
Between the polymorphous layer and the ventricular ependyma is the white substance of the alveus.
The lateral surface of each lamina is directed toward the body and anterior cornu of the lateral ventricle, and is covered by the ependyma of that cavity.