The Erk1/2 and p38 MAPK pathways mediate CXCL10 expression in stimulated astrocytes. A) Western Blot analysis of cytosolic lysates from untreated and virus and cytokine treated A172 astrocytes was conducted at various time points using antibodies against the phosphorylated forms of Erk1/2 and p38. An antibody against β-actin was used to reprobe the blots for normalization. (B) Activation of these pathways were shown to be involved in the synergistic increase in CXCL10 protein expression in these cells through inhibition of the Erk1/2 pathway by U0126 and of the p38 pathway by SB203580. Values are mean ± SD from three independent experiments (***, p < 0.001, **, p < 0.01).