Effects of arctigenin on the (A) TNF-α, (B) IL-10, (C) CRP and (D) IL-6 level in acetic acid-induced chronic ulcer. The results are expressed as means ± standard error of the mean (n=10; one-way analysis of variance, followed by the least significant difference test). *P<0.05, **P<0.01 and ***P<0.001 vs. vehicle group; #P<0.05; ##P<0.01. TNF-α, tumor necrosis factor-α; IL, interleukin; CRP, C-reactive protein.