Studies on lung damage and expressions of AQP1/4 in rats exposed to acute high-altitude hypoxia

【Objective】 To investigate the lung damage and regulatory expressions of AQP1/4 in rats exposed to acute high-latitude hypoxia.【Methods】Sixty female Sprague-Dawley rats were randomly divided into control group and hypoxia groups of 6 h,12 h and 24 h.The rats in hypoxia group were put into a specially designed decompression chamber to simulate altitude of 7 000 m.After hypobaric hypoxia exposure,the morphological changes of lung were observed by HE staining,and the water contents in lung were determined by the wet-dry method.The biochemical indicators like LDH and CAT in lung tissue were detected with biochemistry method,and the expressions of AQP1 and AQP4 in lung tissue were determined individually by Western blot.【Results】The morphological changes of lung in hypoxia groups by HE staining revealled different degrees of cellular injury,including edema of lung epithelial cell,thickening of alveolar wall and enlarge of micrangium.With the increasing duration of hypoxia,the degree of lung damage became serious.Compared with control group,the water contents in lung were remarkably increased in hypobaric hypoxia groups(P 0.01).With the injure duration increased,the water contents were increased remarkably.Compared with control group,the activities of LDH were remarkably increased(P 0.01),and the activities of CAT were creased(P 0.05 or P 0.01) in rats serum of hypoxia groups.Compared with control group,the expressions of AQP1 and AQP4 in lung tissue were significantly increased(P 0.01) after hypobaric hypoxia exposure,and the up-regulation of AQP1 and AQP4 wereenhanced with the increasing duration of hypoxia.【Conclusion】Acute high-altitude hypoxia causes the severe damages of lung tissue,such as cerebral edema,which is correlated with up-regulated expressions of AQP1 and AQP4.