Department of Anaesthesia & Pain Medicine, Royal Perth Hospital, Perth, WA 6847, Australia.
Free Radic Biol Med. 2011 Sep 15;51(6):1235-9. doi: 10.1016/j.freeradbiomed.2011.06.026. Epub 2011 Jun 27.
Reperfusion injury is characterized by significant oxidative stress. F(2)-isoprostanes (F(2)-IsoP's) and isofurans (IsoF's), the latter preferentially produced during increased oxygen tension, are recognized markers of in vivo oxidative stress. We aimed to determine whether increasing oxygen tension during reperfusion modified levels of plasma total IsoF's and F(2)-IsoP's. Forty-five patients undergoing upper-limb surgery were randomized to receive inspired oxygen concentrations of 30, 50, or 80% during the last 15 min of surgery. Venous blood samples were taken before the change in inspired oxygen, after 10 min (before reperfusion), and after 15 min (5 min after reperfusion). IsoF's and F(2)-IsoP's were measured by gas chromatography-mass spectrometry. Venous oxygen tension and hemoglobin concentrations were also measured. Plasma IsoF and F(2)-IsoP levels in the 50 and 80% O(2) groups were not significantly different from those of the 30% O(2) group. In secondary analyses, using data combining all groups, levels of IsoF's, but not F(2)-IsoP's, associated with higher venous oxygen tension (P=0.038). Hemoglobin negatively modified the influence of oxygen tension on levels of IsoF's (P=0.014). This study has shown, for the first time, that plasma IsoF levels associate with higher oxygen tension in a human model of reperfusion, and this effect is significantly attenuated by hemoglobin.
再灌注损伤的特征是显著的氧化应激。F2-异前列腺素（F2-IsoP's）和异呋喃（IsoF's），后者在氧张力增加时优先产生，是体内氧化应激的公认标志物。我们旨在确定再灌注过程中增加氧张力是否会改变血浆总 IsoF 和 F2-IsoP 的水平。45 名接受上肢手术的患者被随机分配在手术的最后 15 分钟内接受 30%、50%或 80%的吸入氧浓度。在改变吸入氧之前、在 10 分钟后（再灌注前）和在 15 分钟后（再灌注后 5 分钟）采集静脉血样本。通过气相色谱-质谱法测量 IsoF 和 F2-IsoP。还测量了静脉血氧分压和血红蛋白浓度。在 50%和 80%O2 组中，IsoF 和 F2-IsoP 水平与 30%O2 组无显著差异。在使用所有组数据的二次分析中，IsoF 水平与较高的静脉血氧分压相关（P=0.038），但 F2-IsoP 水平没有。血红蛋白对氧分压对 IsoF 水平的影响有负向修饰作用（P=0.014）。本研究首次表明，在再灌注的人体模型中，血浆 IsoF 水平与较高的氧分压相关，而血红蛋白显著减弱了这种作用。
