肺表面活性物质磷脂在急性肺损伤时的变化(英文)

使用不同剂量(2、4、6 mg/kg)的N-亚硝基-N-氨基甲酸乙酯(NMU)诱发大鼠急性肺损伤。分析了在急性肺损伤情况下大鼠肺成份、即肺泡游离细胞成份、细胞外肺表面活性物质成份,层状体和微粒体成份的磷脂特性及其变化。以6mg/kg给大鼠皮下注射NMU后第2天,肺泡空间成份的磷脂含量明显减少,细胞内成份没有变化,而在4mg/kg的剂量下未见到类似的结果,甚至在2mg/kg时磷脂的含量稍有增加。肺各成份中磷脂酰胆碱没有受到NMU的影响,但磷脂酰肌醇和鞘磷脂增多,磷脂酰甘油减少,即PG/PI的比率明显降低,PC/SM的比率也有所下降。

CHANGES OF SURFACTANT PHOSPHOLIPIDS IN ACUTE ALVEOLAR INJURY IN THE RAT

We analyzed phospholipids in lung subfractions, i.e. alveolar free cell fraction, extracellular pulmonary surfactant fraction, intracellular pulmonary surfactant fraction(lamellar bodies)and microsome fraction, of rats treated with different doses (2, 4 and 6mg/kg body wt.) of N-nitroso-N-methylurethane (NMU). The contents of phospholipid were significantly decreased in alveolar space-fractions, but not in intracellular fractions at 2 days after NMU-administration (6mg/kg body wt.) in acute alveolar injury state. Such changes in the phospholipids were not remarkable in less severe lung injury state(4mg/kg body wt. NMU-administration), and those seemed to rather increase in the recovery state(2mg/kg body wt. NMU-administration). Although the percentage of phosphatidylcholine (PC) in lung subfractions was not altered significantly by lung injury with NMU. There were a significant decrease in phosphatidylglycerol (PG), and increases in phosphatidylinositol (PI) and sphingomyelin (SM) in some lung subfractions. Thus, the PG/PI ratio was significantly decreased in response to NMU. The PC/SM (L/S)ratio was also decreased in surfactant fractions.