EFFECTS OF BASIC FIBROBLAST GROWTH-FACTOR IN RETINAL ISCHEMIA

Purpose. Basic fibroblast growth factor (bFGF), a 17- to 24-kDa protei n known to be essential for the survival of neurons, induced fiber out growth of ganglion cells in cultures of rat retina and rescued photore ceptor cell loss in the retina of Royal College of Surgeon rats. The a uthors evaluated the efficacy of bFGF in rescuing the neuronal loss in rat retina after retinal ischemia. Methods. Retinal ischemia was indu ced in 29 eyes of 17 albino Lewis rats by increasing the intraocular p ressure to 110 mm Hg for 45 minutes via an intracameral catheter. A to tal of 800 ng of bFGF was delivered into the anterior chamber at the t ime of induction of ischemia. Sixteen eyes of nine rats received bFGF, and 13 eyes of eight rats received heparin in phosphate-buffered sali ne as vehicle control. The animals were euthanized 7 or 14 days after reperfusion. Results. Morphologic examination of the retinas at both t ime points showed that necrosis of the retinal ganglion cells (RGCs) a nd thinning of the inner plexiform and inner nuclear layers were less severe in the bFGF-treated eyes than in the vehicle-treated eyes. On m orphometric examination, 7 days after reperfusion, the mean thickness of the inner retinal layers and the RGC counts on flat preparations of retina in both the posterior and the peripheral portions of the retin a were significantly higher in the bFGF-treated eyes than in the vehic le-treated eyes (P < .02). At 14 days, similar beneficial effects were noted in all morphometric parameters, except RGC counts in the poster ior pole. Conclusion. These results demonstrate that bFGF partially pr otects the RGCs and other inner retinal elements from ischemic injury.