The neuroprotective effects of FGF-2 in neuron-microglia co-cultures. (A) Neuronal cultures were also treated with Glu and FGF-2. Neurons were stained with anti-MAP-2 antibody (green), and microglia were stained with a Cy5-conjugated anti-CD11b antibody (red). Scale bars, 50 μm. (B) The neuronal survival rate was calculated as the percentage of intact neurons in the treated sample relative to the untreated sample. The columns indicate mean with SEM from three independent experiments. * indicates significant differences compared with untreated neuronal cultures (***: P < 0.001); + indicates significant differences compared with untreated neuron–microglia co-cultures (+++: P < 0.001) by one-way ANOVA with Tukey’s post-hoc test. (C) After treatment with 20 μM Glu and 100 ng/ml FGF-2, the inhibitory effects of FGFR were evaluated using FGFR blockers or each anti-FGFR neutralizing antibody (PD, pan-FGFR blocker, 1 μM PD173074; SU, selective FGFR1 blocker, 500 nM SU11652; aR2, anti-FGFR2 antibody; aR3, anti-FGFR3 antibody; aR4, anti-FGFR4 antibody; aR5, anti-FGFR5 antibody; or isotype-matched IgG control). (D) The neuronal survival rate was calculated. The columns indicate the means with SEM from three independent experiments, each of which included the analysis of ten randomly selected fields. Significant differences compared with FGF-2-treatment were noted. **: P < 0.01, ***: P < 0.001 (one-way ANOVA with Tukey’s post-hoc test).