氧化-抗氧化失衡对大鼠肠缺血再灌注后肺脏器损伤的影响

Effects of impaired oxidation-antioxygen system on lung injury induced by gut ischemia-reperfusion in rats

目的:观察氧化-抗氧化失衡对大鼠全肠道缺血再灌注(GIR)后肺损伤的影响。方法:36只Wister大鼠随机分为缺血前30min、GIR后3、6、24、48h和72h共6组(每组6只),采用夹闭肠系膜前动脉(时间60min)技术复制GIR损伤大鼠模型。观察各时相点血浆中谷胱苷肽(GSH)、维生素C(VC)和脂质过氧化物(MDA)的含量,总抗氧化能力(T-AOC)和谷胱苷肽过氧化物酶(GSH-PX)和超氧化物歧化酶(SOD)活力的变化以及肺组织中GSH、VC和MDA的含量,T-AOC、GSH-PX活力的变化,同时观察组织湿干重比值(W/D)的变化。结果:成功复制了大鼠GIR模型,GIR损伤可引起,(1)再灌注后各时相点血浆GSH和VC含量明显下降,T-AOC和GSH-PX活性呈显著降低,血浆MDA水平显著上升,与缺血前比较均有显著的统计学差异(均P<0.01);血浆SOD的活性有上升,但与缺血前比较无统计学差异;(2)肺组织的GSH和VC含量的下降、T-AOC和GSH-PX活力的明显下降,而MDA明显增加,与缺血前比较均有显著的统计学差异(P<0.01或P<0.05);(3)组织W/D均显著高于缺血前水平(均P<0.01)。(4)血浆抗氧化系统损害与肺抗氧化系统损害关系密切(P<0.05～0.001),肺W/D的变化不仅与血浆抗氧化系统损害如MDA、GSH、VC、GSH-PX(P<0.05～0.001)密切相关,并且与肺抗氧化系统损害如VC、GSH-PX、MDA(P<0.05～0.001)也密切相关。结论:大鼠GIR后,全身性抗氧化系统紊乱导致肺抗氧化系统损害及脂质过氧化产物增加,机体氧化与抗氧化的失衡在肺损伤过程中发挥重要作用。

Objective To investigate the effects of impaired oxidation-antioxidation balance on lung injury induced by intestinal isehemia-reperfusion （IIR） in rats. Methods A murine model of IIR was established by clamping superior mesenteric artery for one hour. 36 wister rats were randomized to blank group （30 min before IIR, n = 6） and RIR group. The GIR group was further divided into five subgroups （3, 6, 24, 48, and 72 hours after IIR, n = 6）. At different time points, acitivities of SOD and GSH-PX, levels of GSH, VC, and MDA, and T-AOC in plasma were detected, so were those except SOD in the lung tissues. The W/D lung weight ratio was determined. Results The model of IIR was successfully constructed. Plasma levels of GSH and VC, GSH-PX activity, and T-AOC were significantly lower in the five subgroups than in the blank group （P 〈 0.01 for all comparisons）, while plasm MDA level was markedly higher （P 〈 0.01 ）; plasma SOD activity was increased, with no statistical differences. As compared with the blank group, GSH-PX activity, levels of GSH and VC, and T-AOC were decreased evidently in the lung tissue in the five subgroups, but MDA level was increased remarkably （P 〈 0.01 or P 〈 0.05） ; the W/D lung weight ratio was elevated notably （P 〈 0.01 ）. The change in the W/D weight ratio was closely associated with the impaired oxidation-antioxidation system not only in plasma （MDA, GSH,VC, and GSH-PX） but also in the lung tissue （VC, GSH-PX, and MDA） （P 〈 0.05 - 0.001 for all comparisons）. There was a close relation between plasma and lung impaired oxidation-antioxidation system （P 〈 0.05 0.001 ）. Conclusions In rats with IIR, systemic impairment of of oxidation-antioxidation results in injury to lung oxidation-antioxidation system and in an increase in lipid peroxidation products. The impaired oxidation-antioxidation balance plays an important role in the development of lung injury.