(A) Relative expression levels of Tlr4, Gfap, and Iba1 1, 3, and 5 days after AEW treatment. *P<0.05, **P<0.01, **P<0.001, compared with corresponding vehicle control, n = 4 mice per group. (B) Relative expression levels of Gfap and Iba1 in the dorsal horn of WT and Tlr4−/− mice 5 d after AEW treatment. *P<0.05; #P<0.05, n = 5 mice per group. Note that dry skin induces Tlr4-dependent Gfap expression. (C) Relative expression of Tlr4, Gfap, and Iba1 in cervical spinal cord dorsal horn 24 h after intrathecal LPS (10 μg) injection. Data are presented as means ± S.E.M. *P<0.05, compared with corresponding vehicle control, Student’s t test; n = 4 mice per group.