RESUMO
Optic nerves were dissected from 7-day-old Sprague-Dawley rats, dissociated with collagenase and trypsin, and cultured on poly-L-lysine coated glass coverslips. Cultures were grown in the B-S medium (Bottenstein and Sato, 1979) containing 0.5% fetal calf serum(FCS). All of the coverslip cultures were divided into 4 groups: i. e. Ⅰ, "Ⅰ+GMF", Ⅱ, and "Ⅱ+GMF". Optic nerve glial cells were cocultured with glioblast monolayers in both group Ⅱ and group "Ⅱ+GMF". Glia maturation factor (GMF) was added to the medium in a concentration of 250 ng/ml for group "Ⅰ+GMF" and group "Ⅱ+GMF". No GMF was added to the medium in both group Ⅰ and group Ⅱ. The coverslip cultures were treated with indirect immunofluorescence to identify the cell types of optic nerve. Cells were double-labled with monoclonal gotibody A2B5 and anti-galactocerebroside(GC) monoclonal antibody, or A2B5 and anti-glisl fibrillary acidicprotein (GFAP) antibody. The bipotential glial progenitor cells (A2B5~+, GC~-; or A2B5~+, GFAP~-), mature oligodendrocytes (A2B5~-, GC~+), immature oligodendrocytes(A2B5~+, GC~+), type 1 astrocytes (A2BS~-, GFAP~+) and type 2 astrocytes (A2B5~+, CFAP~+) can be distinguished.After 5 days in culture, the number of cells in group "Ⅱ+GMF" showed a significant increase (P