Prolonged Protective Effect of Basic Fibroblast Growth Factor–Loaded Microparticles in Royal College of Surgeons (RCS) Rats

Abstract

Abstract: : Purpose: To investigate the protective effect of basic fibroblast growth factor–loaded microparticles (bFGF–MPs) against photoreceptor degeneration in Royal College of Surgeons (RCS) rats. Methods: Three week–old RCS rats received intravitreal injections of phosphate– buffered saline, free bFGF (2.5 µg) and bFGF–MPs (0.5 or 2.5 µg). Electroretinograms (ERGs) were recorded 4 and 8 weeks after injection. At the end of the experiment, retinas were prepared for light microscopy or immunocytochemical staining with antibodies to rod opsin, S and M cone opsins, and glial fibrillary acidic protein. Cell death was examined with the TUNEL method. Results: In the bFGF–MPs–treated eyes, the number of cones was larger and the number of TUNEL–positive cells was smaller than in the free bFGF–treated eyes 8 weeks after injection (p<0.05). Amplitudes of ERG b–waves 8 weeks after injection, however, did not differ between the free bFGF–treated eyes and the bFGF–MPs–treated eyes. Conclusions: These results suggest that bFGF–MPs have a prolonged protective effect against photoreceptor degeneration in RCS rats.

Keywords: photoreceptors • neuroprotection • drug toxicity/drug effects