缺血预处理联合缺血后处理对肺移植中缺血再灌注肺损伤的影响

背景:研究显示缺血预处理和缺血后处理在缺血再灌注肺损伤中均具有明显的保护作用。目的:观察缺血预处理联合缺血后处理对肺移植中缺血再灌注损伤的累积保护效应。方法:将40只SD大鼠随机等分为假手术组、模型组、缺血预处理组、缺血后处理组和联合处理组。后4组建立缺血再灌注肺损伤动物模型,缺血预处理组、缺血后处理组和联合处理组在造模前或/和造模后反复3次阻断开放左侧肺门。结果与结论:与缺血预处理组和缺血后处理组相比,联合处理组大鼠肺组织的干质量比、丙二醛和髓过氧化物酶降低(P<0.05),而肺组织中超氧化物歧化酶活性升高(P<0.05),肺组织病理损伤程度明显减轻;缺血预处理组与缺血后处理组大鼠肺组织超氧化物歧化酶活性、丙二醛水平及髓过氧化物酶活性接近(P>0.05),且肺组织病理损伤程度基本相似。而且缺血预处理与联合处理组中超氧化物歧化酶、丙二醛和髓过氧化物酶水平呈正相关。提示缺血预处理和缺血后处理联合应用对于减轻中性粒细胞的侵润和激活及氧化反应对于肺组织的损伤有明显的累积保护效应,从而可以更好的减轻肺缺血再灌注损伤程度。

Effect of ischemic preconditioning combined with ischemic postconditioning on ischemia reperfusion injury during lung transplantation

BACKGROUND:Studies find that ischemic preconditioning and ischemic postconditioning both have obvious protective effects on the ischemia-reperfusion-induced lung injury.OBJECTIVE:To explore the cumulative protection effects of ischemic preconditioning combined with ischemic postconditioning on the ischemia reperfusion injury during lung transplantation.METHODS:A total of 40 SD rats were randomly divided into sham operation group,model group,ischemic preconditioning group,ischemic postconditioning group and combined ischemic preconditioning and ischemic postconditioning group.Lung ischemic reperfusion injury model in rats was constructed in the latter four groups.The left hilus pulmonis in rats of the ischemia preconditioning group,ischemic postconditioning group and combined ischemic preconditioning and ischemic postconditioning group was blocked and opened for three circles before modeling or/and after modeling.RESULTS AND CONCLUSION:Dry weight ratio,the acitivity of myeloperoxidase and the level of malondialdehyde in rat lungs of the combined ischemic preconditioning and ischemic postconditioning group were markedly lower than those in the ischemic preconditioning group and ischemic postconditioning group(P < 0.05);while the activity of superoxide dismutase was significantly higher in the combined ischemic preconditioning and ischemic postconditioning group than those in the ischemic preconditioning group and ischemic postconditioning group(P < 0.05);the pathological injury of the lungs reduced significantly.The activity of superoxide dismutase,the level of malondialdehyde and the activity of myeloperoxidase in rat lungs of the ischemic preconditioning group and ischemic postconditioning group were close to each other(P > 0.05);and the pathological injury of the lungs were close to each other.The levels of the superoxide dismutase and malondialdehyde in the ischemic preconditioning group and combined ischemic preconditioning and ischemic postconditioning group were positively correlated with myeloperoxidase level.These findings indicate that ischemic preconditioning combined with ischemic postconditioning have an obvious cumulative protection effect on lung tissue injury induced by the neutrophil infiltration,activation and oxidation,therefore it can further reduce the lung injury after ischemia reperfusion.