Fig. 2. (  A ) Mean neutrophil count in peripheral blood at baseline and 1 and 4 h after lipopolysaccharide or saline injections. Asterisks indicate significant differences  versus baseline in animals injected with lipopolysaccharide while mechanically ventilated (MV-LPS) or breathing spontaneously (SB-LPS). *  P < 0.001 using repeated-measures analysis of variance. (  B ) Mean neutrophil count in the bronchoalveolar lavage fluid (BAL) performed at the end of the experiment in the three groups. The three treatment groups were statistically different using the Kruskal–Wallis test. The MV-LPS group differed significantly from the other groups as assessed by the  post hoc multiple comparison procedure; *  P < 0.05  versus MV-saline and SB-LPS.