Abstract: Objective To investigate the mechanism that bFGF promotes the regeneration of injured optic nerve and induces dedifferentiation of glial cells in it. Methods Fifty-five adult male SD rats were randomly divided into 3 groups as normal control group, injury group and bFGF group. At day 7 post operation, optic nerves from injury group and bFGF group were detected by gene chip and real-time PCR. At day 7, 14 post operation, optic nerves were harvested and detected by HE staining and immunohistochemistry. Results Compared with the injury group, there were 645 genes expression up-regulated and 458 genes down-regulated including genes related neural stem cell or precursor cell neural development, proliferation, apoptosis, chromatin configuration, transcription regulation, signal transduction, neural growth and so on in the bFGF group. There were bigger nuclei, more cells, more immunoreactivity of nestin, extracellular signal-regulated kinase(Erk1/2), glial fibrillary acidic protein(GFAP), and myelin basic protein(MBP) in the distal optic nerves and more immunoreactivity of neurofilament(NF) in the proximal optic nerves in the bFGF group than that in the injury group.Conclusion bFGF could promote the proliferation of neuroglia cells, dedifferentiation of neural glias and improve the microenvironment to favour the regeneration of injured optic nerve.

Key words: Optic nerve, Injury, bFGF, Glia, Dedifferentiation, Gene chip, Immunohistochemistry, Rat