山羊烟雾吸入伤后早期肺损伤与活性氧变化的关系

本文通过慢性肺淋巴瘘,动态观察了清醒山羊(N=15)严重烟雾吸入伤后早期肺损伤与活性氧变化的关系。实验观察6h。检测SOD活性作为反映O_2~-的变化;EVLW、QL、L/P等作为反映肺损伤的指标。 实验结果表明,伤后均较早出现严重低氧血症、代谢性酸中毒合并呼吸性碱中毒,EVLW及QL伤后1h即明显增加,光镜下见肺间质和肺泡水肿。说明实验动物伤后出现了肺水肿和急性呼吸功能不全。在EVLW及QL增加的同时,CL、L/P及肺血管蛋白漏出量也增加,EVLW与L/P的变化密切相关。提示肺水肿主要系血管通透性增加所致。伤后肺淋巴液、动脉血活性氧变化比静脉血早,动脉血活性氧水平高于静脉血;肺组织、肺灌洗液活性氧及肺淋巴SOD清除重伤后均立即增加,表明吸入伤后活性氧立即增加,且主要来自肺部。活性氧的变化高峰与肺损伤程度的加重变化规律一致,且呈线性关系。提示活性氧可能参与了烟雾吸入伤后早期肺损伤、肺水肿发生和发展的作用。

The Relationship between Active Oxygen Radicals and Early Lung Injury after Smoke Inhalation Injury in Goats

This study observed the relationship between active oxygen radicals and early lung injury after smoke inhalation injury in awake goats (N = I5) with chronic lung lymph fistular. We measured superoxide dismutase (SOD) to demonstrate the active oxygen radicals; Lung lymph flow (QL), lung lymph/plasma total protein and albumin ratio (L/P) , lung lymph total protein clearance (CL) , lung transvascu-lar protein flux, extravascuiar lung water (EVLW) , as well as PaO2 as parameters indicating lung injury.The result demonstrated that during the earlier postinjury period the injuried animals were suffering from hypoxemia, matabolic acidosis and respiratory alkalosis. EVLW and QL increased sharply during the first hour. Interstitial and alveolar edema were seen under microscope. 'These results indicated that the animals develop lung edema and acute respiratory failure. Changs of QL and EVLW were similar to L/P, CL and lung transvascular protein flux; the correlation between L/P and EVLW was significant. These data showed that the pulmonary edema was mainly a permeability one. Changes of active oxygen radicals of lung lymph fluid and arterial blood were earlier than that of venous blood; and active oxygen radicals of arterial blood was slightly higher than that of venous blood. The active oxygen radicals in pulmonary tissue and fluid of lung lavage and the lung lymph SOD clearance increased immidiatly in postinjury. These data suggested that active oxygen radicals were increased and produced in lungs. The active oxygen radicals changed with EVLW, QL, L/P and lung transvascular protein fluxi the correlation between EVLW and active oxygen radicals in pulmonary tissue, fluid of lung lavage, lung lymph SOD clearance and lung transvascular protein flux were all significant. These observations showed that early after smoke inhalation injury active oxygen radicals played a possible role in the development and progression of lung injury and pulmonary edema.