Pacht E R, Kindt G C, Lykens M G
Department of Medicine, Ohio State University, Columbus 43210.
Crit Care Med. 1992 Oct;20(10):1441-7. doi: 10.1097/00003246-199210000-00013.
To determine if bronchoalveolar lavage fluid is a more potent antioxidant after acute lung injury in a sheep model compared with the baseline condition.
Nonrandomized, controlled study, with repeated measures.
University research laboratory.
Seven healthy adult sheep (25 to 50 kg) were studied with five experimental sheep and two control sheep.
Sheep with lung-lymph fistulas were used to study the antioxidant activity of serum, lymph, and bronchoalveolar lavage fluid, both at baseline and after the iv infusion of endotoxin and subsequent induction of acute lung injury. Antioxidant activity was measured, and it reflects the ability of serum, lymph, and bronchoalveolar lavage fluid to inhibit lipid peroxidation.
When compared at several volumes, bronchoalveolar lavage fluid after acute lung injury was a more potent inhibitor of lipid peroxidation than bronchoalveolar lavage fluid at baseline. In contrast, antioxidant activity in both serum (69.6 +/- 4.5% vs. 47.2 +/- 4.6%; p = .001) and lymph (45.0 +/- 2.3% vs. 31.9 +/- 1.2%; p = .001) decreased with acute lung injury.
These findings suggest that the alveolar fluid after acute lung injury possesses enhanced antioxidant activity that is likely due to the influx of serum proteins. Thus, the high permeability pulmonary edema of acute lung injury, while detrimental to gas exchange, may be beneficial in preventing further oxidant-mediated lung injury.
确定在绵羊模型中，与基线状态相比，急性肺损伤后支气管肺泡灌洗液是否具有更强的抗氧化能力。
非随机对照研究，采用重复测量。
大学研究实验室。
七只健康成年绵羊（体重25至50千克），其中五只用于实验，两只作为对照。
使用患有肺淋巴瘘的绵羊，在基线状态以及静脉注射内毒素并随后诱发急性肺损伤后，研究血清、淋巴液和支气管肺泡灌洗液的抗氧化活性。测量抗氧化活性，其反映血清、淋巴液和支气管肺泡灌洗液抑制脂质过氧化的能力。
在多个体积水平进行比较时，急性肺损伤后的支气管肺泡灌洗液比基线状态下的支气管肺泡灌洗液更能有效抑制脂质过氧化。相比之下，急性肺损伤时血清（69.6±4.5%对47.2±4.6%；p = 0.001）和淋巴液（45.0±2.3%对31.9±1.2%；p = 0.001）中的抗氧化活性均降低。
这些发现表明，急性肺损伤后的肺泡液具有增强的抗氧化活性，这可能是由于血清蛋白的流入。因此，急性肺损伤的高通透性肺水肿虽然对气体交换有害，但可能有助于预防进一步的氧化介导的肺损伤。
