Fig. 7. Additive effects of growth factor combinations on glutamate uptake in cultured astrocytes. Astrocytes were treated with each growth factor alone or together with others for 36 hours. A combination of IGF-1 with either bFGF or EGF showed an additive effect on glutamate uptake activity, but a combination of bFGF and EGF did not. (*p<0.05 vs bFGF alone; ^#p<0.05; ^##p<0.01 vs IGF-1 alone; ^$p<0.05 vs EGF alone; ^!!p<0.01 vs a combination of bFGF and EGF, Tukey’s test following ANOVA). Data represent means±s.e.m. of 4 cultures.