Effect of OR on MAPK phosphorylation in macrophages: (A) ERK, (B) p38 and (C) JNK. RAW 264.7 cells were treated with OR for 30 min before being incubated with LPS for 30 min. Cell lysates were analyzed by Western blotting using specific antibodies. Data represent mean ± SE values of duplicate determinations from three independent experiments. *p < 0.01 and **p < 0.001 were calculated from comparisons with the LPS-stimulation value.