[Postnatal cellular pleomorphosis in retinal pigment epithelium].

Abstract

Selected features of cell morphology of the retinal pigment epithelia (RPE) were compared in newborn (42 eyes) and adult albinotic rats (34 eyes) at the age of 9 months. The RPE of newborn rats was found to consist of nearly homeomorphous, hexagonal, mononucleate, and relatively small cells (monomorphism). Minimal regional differences were found to exist. In adult albinotic rats the density of the RPE cell population was found to be considerably reduced, but the cells and nuclei were generally enlarged. A high percentage of RPE cells was found to contain two nuclei, and as a rule there were always some cells with three, four or even more nuclei. The picture of the cell mosaic was characterized by marked pleomorphism with regionally determined graduation. Pleomorphous changes were more pronounced in the central than in the more peripheral areas. The genesis and dynamics of cellular pleomorphism are also discussed.