FIG 4 .

Streptomycin treatment markedly enhances mucosal Nos2 mRNA levels. Groups of mice (n = 4) were mock treated (LB) or streptomycin treated (LB plus streptomycin), and RNA was extracted from their ceca 1 or 4 days after inoculation. Transcript levels of Cxcl1 (A), Cxcl2 (B), Ccl2 (C), Ccl8 (D), Lcn2 (E), and Nos2 (F) were determined by quantitative real-time PCR. Bars represent the geometric means ± the standard errors of n-fold changes in mRNA levels of the streptomycin-treated group versus the mock-treated group at each time point. The statistical significance of differences between groups is indicated at the top of each graph. NS, not statistically significantly different.