Constitution of the ependyma in the chicken telencephalon

Regional differences in the ependyma of the optic tectal ventricle of adult zebrafish with structures referring to brain hydrodynamics

Classical electron microscopic morphological studies provide detailed ultrastructural information, which may lend insights into cellular functions. As a follow-up to our morphological investigation of the adult zebrafish (Danio rerio) optic tectum, in this study, we have analyzed the ependymal structures lining the surfaces of the tectal ventricle: the torus, tegmental surface of the valvula cerebelli and the periventricular gray zone of the optic tectal cortex. We used toluidine blue stained plastic (semithin) sections for light microscopy and scanning electron microscopy. Our morphological findings of gated entrances and/or egresses indicate that, at least in the adult zebrafish brain, there may be a bidirectional direct flow communication between the ventricular cerebrospinal fluid and the parenchymal interstitial fluid.

Vimentin in ependymal and subventricular proliferative zone cells of rat telencephalon

Ependymal cells of cerebral ventricles are the most probable candidate progenitor cells. We studied ependymal and subventricular zone cells expressing intermediate filament protein vimentin. The results suggest that the ventricular ependyma represent a homogenous cell population. Some ependymocytes have long processes contacting with blood vessels, which makes them similar to tanycytes of the third cerebral ventricle. New data on the structure of ependymocyte processes attest to their active involvement into creation of a special microenvironment for neural stem cells of the subventricular proliferative zone.