Abstract: AIM: To investigate the effects of sevoflurane inhalation on the ultrastructure changes in lung tissue during ischemia-reperfusion lung injury in rabbits and explore the underlying mechanisms.METHODS: Seventy two Japanese long-ear white rabbits weighing 2.5-3.0 kg were randomly divided into four groups (n =18):sham operation group S;IR group in which hilum of left lung was clamped for 45 min and then unclamped for reperfusion for 120 min;Sev-IR group in which 1MAC sevoflurane was inhaled for 30 min before ischemia;Sev-S group 1MAC in which sevoflurane was inhaled for 30 min without IR.The ultrastructure changes in lung tissue were observed under electron microscopic at 45 min after pulmonary ischemia, 60 and 120 min of reperfusion.Myeloperoxidase of lung was measured at 120 min of reperfusion.RESULTS: In group IR:pneumonocyte Ⅰ and vascular endothial cell became swollen and deteriorated;there were reduced microvilli on the surface of pneumonocyte Ⅱ, and Ⅱ type alveolar epithelial cells were swollen or vesicular and plenty of polymorphonuclear neutrophils stayed in capillary chambers.The increased levels of myeloperoxidase in group IR and group Sev-IR were significantly higher than those in group S, but compared with group IR, group Sev-IR could inhibit the increase of myeloperoxidase after 120min of reperfusion (P <0.05).CONCLUSION: Sevoflurane attenuates the IR-induced pulmonary ultrastructural changes, possibly through an inhibition of polymorphonuclear neutrophil recruitment into the lung.

Key words: sevoflurane, lung, reperfusion injury, ultrastructure