Effect of butyrate on the nuclear expression of NF-κB in lung tissues of mice with ALI. A., B. and C. Representative Western blots showed the nuclear expression of NF-κB p65 in lung tissues in different groups. D. Mean ± SEM NF-κB p65 optical densitometry from different groups. Pretreatment of butyrate significantly repressed the expression of NF-κB p65 in nucleus at 1, 3 and 6 hours after LPS administration. Data are expressed as mean ± SEM, *P < 0.05 vs. control and butyrate group; #P < 0.05 vs. LPS group.