Purpose: To improve the outcome of injured retina, human recombinant basic fibroblast growth factor (bFGF) was examined for its ability to accelerate healing in laser-injured New Zealand Red rabbits.
Methods: A multi-line argon laser (454 to 514 nm) was used to produce lesions near subretinal hemorrhaging levels. Within 30 minutes after irradiation, eyes were intravitreally injected directly above the lesions with 10 microliters vehicle or 10 micrograms of bFGF in 10 microliters of vehicle. Lesions were evaluated by funduscopy and fluorescein angiography. After 4 days of treatment, animals were killed and eyes examined histologically.
Results: On subsequent days, bFGF-treated lesions were less opaque, smaller in diameter, and less leaky to fluorescein than lesions in the control eyes. Eyes treated with bFGF exhibited reduction in lesion diameter (P < or = 0.001) and in the lesion periphery, decreased loss of photoreceptors (P < or = 0.001), and greater numbers of pigmented epithelial cells, compared to controls. By bromodeoxyuridine incorporation, increased proliferation occurred in fibroblasts, retinal pigmented epithelial cells, and inner retinal glial cells.
Conclusions: These results indicate that bFGF both accelerated ocular tissue repair and also prevented photoreceptor loss. The rescue of photoreceptors by bFGF may occur through direct action on the photoreceptors, or indirectly through effects on other cells in the retina.