RESUMO
<p><b>AIM</b>To investigate the effects of ischemic preconditioning on reperfusion injury of rat lung.</p><p><b>METHODS</b>Rat isolated lungs (n=8 in each group) were stabilized and perfused by Krebs-Henseleit solution on a modified langendorff perfusion apparatus. 36 wistar rats were divided into three groups: ischemic preconditioning group, ischemia/reperfusion group and control group. Mean pulmonary artery pressure, wet/dry ratio, pulmonary surfactant phospholipid and alveolar surface tension in bronchoalveolar lavage fluid and electron microscope were detected.</p><p><b>RESULTS</b>The morphological changes of lung injury were alleviated in the preconditioning group under electron microscope. Wet/dry ratio, mean pulmonary artery pressure and SA/LA ratio were significantly lower in the preconditioning group after ischemic/reperfusion (P < 0.01). Total phospholipid and large aggregate in the BALF were significantly increased in the preconditioning group (P < 0.01). Small aggregate showed no change in three groups. Surfactant activity test showed that surface tension markedly decreased in IPC group (P < 0.01).</p><p><b>CONCLUSION</b>These results indicates that ischemic preconditioning may have a protective effect in ischemic/reperfusion injuries lung by ameliorating the content and function of surfactant phospholipid.</p>