Subject(s)
Capillary Permeability , Dextrans/metabolism , Fluorescein Angiography , Fluoresceins/metabolism , Animals , Columbidae , Molecular Weight , RatsABSTRACT
The occurrence of attachment sites between the basal plasma membrane of the retinal pigment epithelium and its basement lamina have been observed in a variety of animal species, including man. Similar structures connect adjacent basal infoldings of the retinal pigment epithelium. The topographic distribution of such attachment sites and basal infoldings in rat eyes show small differences between the peripapillary, posterior, and peripheral retina. Such attachment sites may help to provide a firm connection between the retinal pigment epithelium and choroid.
Subject(s)
Choroid/ultrastructure , Retina/ultrastructure , Animals , Basement Membrane/ultrastructure , Cats , Cell Membrane/ultrastructure , Choroid Neoplasms/pathology , Desmosomes/ultrastructure , Dogs , Epithelial Cells , Epithelium/ultrastructure , Glaucoma/pathology , Humans , Melanoma/pathology , RatsABSTRACT
Detailed light and electron microscopic examination of early idiopathic preretinal fibrosis lesions showed that the fibrosis consisted of a layer of glial cells on the retinal surface. Two cases supported the clinical observation that a glinting retinal reflex preceded the development of retinal folds and traction lines. In both cases there was a break in the inner limiting lamina through which glial cells migrated and, presumably, proliferated on the retinal surface. There was no evidence for vitreoretinal adhesions. The ultrastructural similarity of the lesion to preretinal glial membranes seen in other disease entities suggested the possibility of a common biochemical stimulus for glial cell migration and proliferation on the retinal surface.
