缺血后处理对供体犬肺再灌注损伤的影响

Influence of ischemic post-conditioning on the lipid peroxidation after lung transplantation in canis

目的观察供体犬肺再灌注后早期脂质过氧化反应的变化，了解缺血后处理对供体犬肺植入后功能的影响。方法随机选取12对比咯犬，组成供、受体，随机分成2组。对照组：6对犬，按常规进行供受体左侧异体单肺移植，不予缺血后处理的干预。缺血后处理组：6对犬，进行供受体常规左侧异体单肺移植，再灌注早期实施3个周期的10s再灌．10s再阻断、总时程1min的缺血后处理。于供肺再灌注后1、2h两个时间点采集供肺标本检测超氧化物歧化酶（SOD）的活性、丙二醛（MDA）的含量。光镜下观察供肺植入后1、2h两个时间点肺组织的病理变化。结果术后实验犬均存活。植入供体肺平均用时（35．92±1．73）min。缺血后处理组在1、2h时间点的供肺组织SOD活性水平较对照组升高、MDA含量较对照组减低，差异有统计学意义（P〈0．05）。缺血后处理组肺组织光镜下观察在各时间点的炎症反应均较对照组的变化轻微。结论缺血后处理可以抑制再灌注时氧自由基的堆积，从而减少供肺的缺血再灌注损伤，改善供肺植入后的功能。

Objective Ischemia-reperfusion injury may occur in the donor lung during lung transplantation. As a response to isehemia-reperfusion injury, ischemie post-conditioning provides an intrinsic protection. The study was aimed at identifying the influence of ischemie post-conditioning on the function of donor lung in dogs by measuring the changes of lipid peroxidation during early reperfusion. Methods Twelve orthotopie left lung transplantations were performed by using 24 paired dogs. The animals were divided randomly into the ischemie post-conditioning group and the control group. For dogs （6 pairs） in the control group, no intervention of isehemic post-conditioning was performed during routine left lung transplantation, for the rest dogs in the ischemie post-conditioning group, 3 cycles of ischemle pest-conditioning with reperfusion（for 10 seconds）-interruption （for another 10 seconds） were performed after implantation of donor lungs obtained routinely. Content of malonaldehyde（MDA） and activity of superoxide dismutase （SOD） in the specimens of donor hmgs were measured with Commassie Brilliant Blue 1 and 2 hours after transplantation, respectively. Meanwhile, fresh pulmonary specimens obtained at different time points were stained with hematoxylin and eesin（HE）. A statistical software SPSS 13.0 was used in the analysis. A significant difference was indicated by P 〈0.05. Results Transplantations were completed in 12 receiver canis, the mean time for anastomoses was（ 35.92 ± 1.73） rain. The contents of MDA in the experimental group was significantly lower than that of control group（ P 〈 0.05） 1 and 2 hours after transplantation. The activity of SOD was significantly higher in the experimental group than that of control group 1 and 2 hours after transplantatien（ P 〈 0.05）. Under the light microscopic examination, the inflammatory changes observed were comparative mild in the ischemic post-conditioning group. Conclusion The accumulation of reactive oxygen species induced by canine lung transplantation may be decreased with ischemic post-conditioning, an intervention that attenuates damage to the donor langs and improves their function during ischemia reperfusion.