Changes in the organization and expression of cytoskeletal proteins during retinal degeneration induced by retinal detachment.
OBJECTIVE
The goal of this study was to determine the changes in the organization of the retinal cytoskeleton after experimental retinal detachment.


METHODS
Cat retinas were detached from the retinal pigment epithelium and then processed for Western blot analysis and fluorescence microscopy. Proteins examined included glial fibrillary acidic protein (GFAP), vimentin, tubulin, and actin. Sections were viewed using a laser scanning confocal microscope.


RESULTS
GFAP and vimentin: At 1 day after detachment, there was an aggregation of intermediate filaments in the endfoot of Müller cells. At 3 days, intermediate filament containing Müller cell processes could be detected within the subretinal space, and, at 28 days, these processes formed large glial scars in the subretinal space. beta-tubulin: At 3 days after detachment, an increase in immunolabeling could be detected within the Müller cell endfoot and in Müller cell processes within the subretinal space. Actin: At 3 days after detachment, rhodamine-phalloidin staining decreased in the inner segments, the photoreceptor synaptic terminals, and the outer limiting membrane.


CONCLUSIONS
The decrease in labeling of the photoreceptor inner segment and synaptic terminal cytoskeleton may be a key indicator of early changes in photoreceptors after detachment. The increase in cytoskeletal proteins GFAP, vimentin, and tubulin within the retinal Müller cells after detachment may help to stabilize this cell type as it hypertrophies during glial scar formation. Inhibition of this response may aid in the treatment of diseases in which Müller cell hypertrophy plays a role.
Lewis
G P
GP
Neuroscience Research Institute, University of California, Santa Barbara 93106, USA.
Matsumoto
B
B
Fisher
S K
SK
D000818:Animals; D015153:Blotting, Western; D002415:Cats; D003598:Cytoskeletal Proteins / Q000096:biosynthesis*; D003599:Cytoskeleton / Q000378:metabolism* / Q000473:pathology; D004591:Electrophoresis, Polyacrylamide Gel; D005456:Fluorescent Dyes; D018613:Microscopy, Confocal; D010590:Phalloidine; D010786:Photoreceptor Cells / Q000378:metabolism / Q000473:pathology; D012160:Retina / Q000473:pathology; D012162:Retinal Degeneration / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D012163:Retinal Detachment / Q000150:complications* / Q000473:pathology; D012235:Rhodamines
D003598:Cytoskeletal Proteins; D005456:Fluorescent Dyes; D012235:Rhodamines; D010590:Phalloidine