| The neural retina of 16 Rhesus monkeys was surgically detached from its overlying pigmented epithelium for 7 days, resulting in degenerative changes in several types of retinal cells. Changes were marked by disintegration of the photoreceptor outer segments, increases in intermediate filaments in Muller's glia, and proliferative changes in the epithelial layer. After a seven day detachment, regeneration of the tissues was stimulated by reapposing the retina to the epithelial layer. The animals were allowed to recover for various periods of time, regenerating disc outer segment membranes were labeled with {dollar}sp3{dollar}-H-Fucose, and the animals were sacrificed.; The organized membraneous discs of the photoreceptor outer segments, which disintegrated during the detachment interval, began to recover as early as three days post reattachment. By 14 days after reattachment most outer segments had recovered their normal configurations although their absolute length was less than half that of comparable controls. By 150 days of recovery outer segment length in the detached areas did not significantly differ from controls. There appeared to be no differences between macular and peripheral photoreceptors in their capacity for recovery.; {dollar}sp3{dollar}-H Fucose autoradiography demonstrated subnormal but gradually increasing rates of new membrane assembly at the 7, 14, and 30 day recovery timepoints. This data correlated well with the shortened outer segments as well as the pattern of increase in outer segment length found in the morphometric measurements.; Immunocytochemical studies found increases in the intermediate filaments vimentin, and Glial Fibrillary Acidic Protein, (GFAP), in Muller's glia after detachment and reattachment of the retina. Additionally, at 7 and 14 days post-reattachment, vimentin was detected in the retinal pigmented epithelial cells along their basal and lateral surfaces. These changes appeared to continue up to 14 days after the retinas were reattached. After 150 days of recovery the increase in IF's appeared to have been attenuated.; These findings demonstrate that degenerative changes produced by a brief, (7 day), separation of the neural retina from the supportive retinal pigment epithelium can be at least partially reversed if the retina is reattached. |
