Wang P M, Lai-Fook S J
Center for Biomedical Engineering, University of Kentucky, Lexington, KY 40506-0070, USA.
Lung. 1998;176(5):309-24. doi: 10.1007/pl00007613.
The hypothesis of this study is that pleural lubrication is enhanced by hyaluronan acting as a boundary lubricant in pleural liquid and by pleural filtration as reflected in changes in protein concentration with ventilation. Anesthetized rabbits were injected intravenously with Evans blue dye and ventilated with 100% O2 at either of two levels of ventilation for 6 h. Postmortem values of hyaluronan, total protein, and Evans blue-dyed albumin (EBA) concentrations in pleural liquid were greater at the higher ventilation, consistent with increases in boundary lubrication, pleural membrane permeability, and pleural filtration. To determine whether these effects were caused by hyperoxia or anesthesia, conscious rabbits were ventilated with either 3% CO2 or room air in a box for 6, 12, or 24 h. Similar to the anesthetized rabbits, pleural liquid hyaluronan concentration after 24 h was higher in the conscious rabbits with the hypercapnic-induced greater ventilation. By contrast, the time course of total protein and EBA in pleural liquid was similar in both groups of conscious rabbits, indicating no effect of ventilation on pleural permeability. The increase in pleural liquid hyaluronan concentration might be the result of mesothelial cell stimulation by a ventilation-induced increase in pleural liquid shear stress.
本研究的假设是，透明质酸作为胸腔液中的边界润滑剂以及通过通气时蛋白质浓度变化所反映的胸膜滤过作用，可增强胸膜润滑。对麻醉后的兔子静脉注射伊文思蓝染料，并以两种通气水平之一用100%氧气通气6小时。在较高通气水平下，胸腔液中透明质酸、总蛋白和伊文思蓝染色白蛋白（EBA）浓度的死后值更高，这与边界润滑、胸膜膜通透性和胸膜滤过的增加一致。为了确定这些效应是由高氧还是麻醉引起的，将清醒的兔子置于箱中，用3%二氧化碳或室内空气通气6、12或24小时。与麻醉后的兔子相似，在高碳酸血症诱导通气量更大的清醒兔子中，24小时后胸腔液透明质酸浓度更高。相比之下，两组清醒兔子胸腔液中总蛋白和EBA的时间进程相似，表明通气对胸膜通透性没有影响。胸腔液透明质酸浓度的增加可能是通气诱导的胸腔液剪切应力增加刺激间皮细胞的结果。
