Figure 2

Histopathological analysis of leukocyte influx into the lung tissue. (A) Histological analysis of the control mice lungs indicated the absence of leukocytes in the vessels (v) and in the lung tissue. (B) After intestinal ischemia-reperfusion, several transmigrated leukocytes were observed in the lung parenchyma connective tissue (arrows). (C) AnxA1 peptide Ac2-26 treatment prevented leukocytes influx into the lung tissue (arrowheads). Toluidine blue stain. Bar, 10 μm. (D-E) Cell counting in the histological sections. (D) Semi-quantitative analysis showing increase in the intravascular neutrophils after intestinal I/R and after peptide Ac2-26 treatment followed by intestinal I/R. (E) Semi-quantitative analysis showing increase in the transmigrated neutrophils into lung connective tissue after intestinal I/R and reduction after peptide Ac2-26 treatment followed by intestinal I/R. Tissue area was determined by Axiovision Software. (F) MPO activity analysis demonstrated increased number of neutrophils into lung tissue after intestinal I/R and reduction after peptide Ac2-26 treatment followed by intestinal I/R. (G-I) Mice subjected to intestinal ischemia/reperfusion (I/R) had significantly increased pulmonary injury, measured by edema and microvascular leak (hole lung and alveoli). The changes were significantly attenuated by pretreatment with Ac2-26. All data are mean ± SEM from 5 mice per time point. *P < 0.05, **P < 0.01 and ***P < 0.001 versus control group values; #P < 0.05 and ##P < 0.01 versus corresponding intestinal I/R group values.