中文摘要：

目的研究急进高原肺损伤大鼠肺脏超微结构及肺泡液体清除率（alveolar liquid clearance,ALC）的变化规律,并探讨二者间的内在关系。方法将大鼠暴露于高原低氧环境,分别于1、24、48、72 h测定基础ALC,取病理切片观察肺脏超微结构的变化。并对上述结果进行相关分析。结果急进高原大鼠暴露于高原低氧24 h后ALC（22.60±3.41%）与正常大鼠ALC（41.14±9.36%）比较有明显变化（P〈0.05）,内皮细胞出现损伤,而上皮细胞无明显结构变化;48 h时ALC（25.28±6.30%）明显降低（P〈0.05）,肺泡上皮细胞的结构和上皮细胞间的紧密连接并无明显损伤;72 h ALC（45.52±10.05%）无明显变化（P〉0.05）,但肺泡上皮细胞结构被破坏。结论高原低氧致急进大鼠ALC降低,但肺泡上皮屏障结构无明显改变,提示急进高原大鼠肺泡内液体的储积与钠水通道有关。

英文摘要：

Objective To study the ultra- structural and alveolar liquid clearance（ ALC） changes in rats＇ lungs exposed to high altitude,and to investigate the relationship between them. Methods Sixty Wistar rats were randomly divided into four groups. The hypoxic rats were generated by exposure to high altitude. Basal ALC stimulated by terbutaline were measured at 1 h,24 h,48 h and 72 h,respectively. The specimens were examined by electron microscopy. Results After the rats were exposed to high altitude for 24 h,the level of ATC（ 22. 60 ± 3. 41%） showed remarkable difference compared with that of normal rats（ 41. 14 ± 9. 36%）. The capillary endothelial cells had some injury changes while the alveolar epithelial cell showed no obvious change. ATC（ 25. 28 ± 6. 30%） decreased markedly while the alveolar epithelial cells had no obvious structural change at 48 h. At 72 h,the level of ATC（ 45.52 ±10.05%） showed no marked difference compared with that of normal rats,and the alveolar epithelial cells showed marked changes. Conclusion In the setting of mild and moderate lung injury,although ATC is deceased the structure of alveolar epithelial barrier may not necessarily be changed,the storage of liquid with alveolar in rats associated with sodium channel exposed to high altitude.