(A) Mice (n = 4) were given i.c.v. injection with LPS (2.5 µg) alone or injected with AACOCF3 (2 µg) or U0126 (2 µg) 1 hour before LPS stimulation for 1 hour. (B) The in vitro effects of U0126 on PGE2 production and (C) phosphorylation of ERK1/2 and cPLA2α in primary rat astrocytes were determined. Astrocytes (n = 3) were treated with U0126 (01, 1, 2 and 5 µM) for 2 hours before LPS (100 ng/mL) stimulation for up to 24 hours. The PGE2 levels in tissue homogenate at 1 hour after LPS stimulation (A) or culture supernatants at 24 hours after LPS stimulation (B) were determined by using ELISA-based assay as described in methods, the phosphorylation of ERK1/2 and cPLA2α in the cell lysates at 4 hours after LPS challenge (C) were determined by western blot as described in methods. Values represent the mean ± S.E.M. of results from five animals in each group. One symbol, p<0.05; two symbols, p<0.01; three symbols, p<0.001. (#), significant comparisons for LPS versus control ; (*), significant comparisons for U0126 versus LPS; (&), significant comparisons for AACOCF3 versus LPS.