Abstract
Purpose: :
Perfluorocarbon (decalin) is widely used during vitreoretinal surgery. Introduction of decalin into the subretinal space via retinal tears or fixation of the retina following 180 retinotomy exposes photoreceptors and RPE to the decalin. Using immunocytochemistry we examined the effect of decalin on the neural retina in organ culture and the effect on RPE cell viability.
Methods: :
Adult bovine neural retinas were exposed to decalin or balanced saline solution (BSS) for 30min or 60min and cultured in MEM at 10% FCS. After 3 days in culture, the retinas were fixed, embedded in paraffin and stained with H&E for morphological evaluation. Using immunohistochemistry the retinas were analyzed for glial fibrillary acidic protein (GFAP) expression as an indicator of astrocyte and glial cells, vimentin as an indicator of cytoskeletal elements and rhodopsin as a marker of photoreceptors. Effect on RPE cell viability was examined by exposing confluent cultures of RPE cells to decalin or BSS for 30min or 60min and assessing cell viability at 0, 1 h, 1 day and 3 days using the Celltiter Glow luminescent cell viability assay.
Results: :
Histologically retinas exposed to decalin for 30 and 60 minutes showed evidence of significant photoreceptor outer segment degeneration. Immunohistochemical analysis revealed upregulation of GFAP and vimentin in retinas treated with decalin as well as BSS, which was especially prominent in retinas treated for 60 minutes with decalin. Within 1 hour of exposure to BSS and decalin there was significant cell death in confluent cultures of RPE cells specially in the decalin treated cells. However, with continued culture the cells recovered and by day 3 cell numbers had returned to control levels.
Conclusions: :
The result of this study shows that decalin is toxic to neural retina cells as evidenced by photoreceptor degeneration after 30 or 60 minutes exposure. The alteration in the expression of vimentin and GFAP indicate that decalin is toxic to specific neural retinal structures. Decalin also appears to damage RPE cells, however the damage does not appear to be permanent since the cells recover such that within 72 hours cell number returns to the control level.
Keywords: retinal degenerations: cell biology • retinal pigment epithelium • retinal culture