Lung sample ultrastructure was evaluated by electron microscopy. A. The ultrastructural architecture of type II pneumocytes as evaluated by Electron Microscopy with normal lamellar bodies, mitochondria, tight junction, and microvilli was normal in Sham group. B. The perinuclear gap in the type II pneumocytes was widened and showed early stage of apoptosis in the Ischemia group (white arrow head). C, D. Swelling of lamellar bodies (black arrow) in some type II pneumocytes and nuclear membrane blebbing (white arrow head) were shown in the Inhaled NO group. E. Apoptosis was indicated by more extensive nuclear shrinkage, chromatin condensation and margination (white arrow head), whereas plasma membrane and intracellular organelles such as lamellar bodies showed degenerative changes (black arrow) but had an intact surface in the Reperfusion group. F. The type II pneumocyte with lamellar bodies swelling (black arrow), cytoplasmic vacuolation, and irregular nuclear shed into the alveolar space in Reperfusion group.