【摘要】 目的探讨水通道蛋白5(AQP5)在早产大鼠及吸高氧过程中的肺动态表达。方法剖宫术取出孕21d SD早产鼠,于12～24h内随机分为对照组和高氧组。分别在1、4、7、10和14d时提取肺组织,RT-PCR测定AQP5 mRNA表达,免疫组化和Western blot检测AQP5蛋白的表达。结果早产大鼠生后肺组织AQP5表达不断增强,其阳性染色主要定位于Ⅰ型肺泡上皮细胞。高氧暴露1d时,仅肺组织AQP5 mRNA表达显著高于对照组(P<0·05),而高氧暴露4、7、10及14d时,其mRNA及蛋白表达均明显减少(P<0·05或P<0·01)。结论AQP5通过调节肺水平衡,在早产大鼠肺泡化形成的关键时期发挥重要作用;高氧暴露导致AQP5表达下调是促使肺损伤发生、发展的重要因素。更多还原

【Abstract】 Objective To explore the expression of lung Aquaporin5 (AQP5) in premature rats and during the process of inhaling hyperoxia. Methods Gestation 21 day Sprague-Dawley(SD) fetuses (term=22 day) were randomly divideal into control group and hyperoxia group 12～24 h after birth. Hypreoxia group was exposed to about 85% oxygen. After 1 to 14 days of exposure, lung tissue was isolated and AQP5 mRNA was detected by RT-PCR. Immunohistochemistry and Western-blot was used to detect AQP5 protein. Results The expression of lung AQP5 in premature rats persistently increased after birth, and the positive staining was restricted to the typeⅠalveolar epithelial cells. Compared with control group, the AQP5 mRNA in hyperoxia group of day 1 increased significantly (P<0.05), but after exposure to hyperoxia for 4 to 14 days, the AQP5 expression resulted in a decrease of mRNA and protein(P<0.05 or P<0.01). Conclusion AQP5 may play a key role in the alveolar period of premature rats. Hyperoxia down-regulates the AQP5 expression, this might be an important factor for the development of hyperoxia lung injury.更多还原