Fig. 1

Pathologic changes of lung tissues examined by HE staining and TEM. Lung tissues were dissected and performed with HE staining and TEM analysis. a HE staining of the lung tissue sections in the four groups; b TEM results of the tissue sections in the four groups. The HE staining results demonstrated no abnormal changes in the sham group; however, pathological changes happened severely in the IR-C and IR-NS group. The histological damages in IR-RV group were reduced compared with the other two IR groups. The TEM results demonstrated the lung tissue ultrastructure was normal with tightly connected pulmonary capillary endothelial cells, intact basement membrane and integral type I and type II alveolar epithelial cells in sham group. Meanwhile, the mitochondrial cristae, microvilli and the lamellar body were clear. However, the ultrastructure was changed in IR-C and IR-NS groups. Their ultrastructure of lung tissue appeared serious abnormalities. In IR-RV group, reduced injuries were found compared to the other two IR groups