The role of the subependymal plate in the origin of gliomas induced by ethylnitrosourea in the rat brain.

The fine structure of early cell proliferations induced transplacentally by ethylnitrosourea in the rat brain reveals that the cells show features of the undifferentiated cells of the subependymal plate: high nuclear-cytoplasmic ratio, scarity of cell organelles and dominance of free over membrane-bound ribosomes. These findings suggest that most, if not all, gliomas induced by ethylnitrosourea originate from these primitive cells.