高氧对新生大鼠肺泡Ⅱ型上皮细胞上皮钠通道转运功能的影响  

Expression and transport function of epithelial sodium channel in alveolar epithelial type II cells of hyperoxia-exposed neonatal rat

作　　者：纪卫华[1] 聂宏光[2] 富建华[3] 薛辛东[3] 

机构地区：[1]大连市妇产医院新生儿科,116033 [2]中国医科大学药学院,沈阳110001 [3]中国医科大学附属盛京医院儿科,沈阳110004

出　　处：《中国小儿急救医学》2012年第5期498-502,共5页Chinese Pediatric Emergency Medicine

基　　金：基金项目：国家自然科学基金资助项目（30872781）

摘　　要：目的探讨高氧对新生大鼠肺泡Ⅱ型上皮（alveolar epithelial type II，ATⅡ）细胞钠转运功能的影响。方法分离提取新生大鼠ATI／细胞，随机分成高氧组和对照组，分别在氧浓度为85％和21％的细胞培养箱中原代培养。应用Westernblot方法和全细胞膜片钳技术检测高氧暴露后上皮钠通道（epithelial sodium channel，ENaC）蛋白表达变化及高氧对阿米洛利敏感性钠电流的影响。结果高氧使新生大鼠ATⅡ细胞中p—ENaC和y—ENaC表达增加[β—ENaC：（1d：0．43±0．06VS0．32±0．04，P=0．047；2d：0．73±0．06VS0．50±0．08，P=0．019；3d：0．72±0．08VS0．52±0．06，P=0．027）；y-ENaC：（1d：0．64±0．05VS0．53±0．05，P=0．044；2d：0．76±0．03VS0．52±0．04，P=0．001；3d：0．77±0．06VS0．61±0．05，P=0．025）]，同时使阿米洛利敏感性钠电流增强（1d：13．71±2．77VS8．92±1．38，P〈0．001；2d：29．12±11．03VS10．41±1．80，P〈0．001），而对a-ENaC表达表现出一定的抑制作用（1d：0．31±0．05VS0．46±0．05，P=0．025；2d：0．30±0．01VS0．38±0．02，P=0．002；3d：0．37±0．06VS0．37±0．08，P=0．983）。结论高氧促进了AT II细胞ENaC钠转运功能，ENaC功能障碍并非高氧暴露后肺水肿发生的主要原因。Objective To investigate the effect of hyperoxia on the expression and transport function of epithelial sodium channel （ENaC） in neonatal rat alveolar epithelial type U（ AT II ） cells. Methods AT II cells were isolated from neonatal rats, and primarily cultured under hyperoxic or normoxic conditions. Western blot was applied to examine the ENaC expression, and the amiloride-sensitive Na ＋ currents were recorded u- sing the whole-cell patch clamp technique. Results Hyperoxia upregulate the expression of β-ENaC and y- ENaC subunits in the neonatal rat AT II cells（ β-ENaC：1 d：0. 43 ±0. 06 vs 0. 32 ±0. 04,P =0. 047;2d ：0. 73 ± 0. 06 vs 0. 50 ± 0. 08,P = 0. 019 ;3 d-0.72 ± 0. 08 vs 0. 52 ± 0. 06, P = 0. 027 ; y-ENaC： 1 d ：0. 64 ± 0. 05 vs 0.53±0.05,P=0.044;2d：0.76±0.03 vs0.52±0.04,P=0.001;3 d：0.77 ±0.06 vs0.61 ±0.05,P= 0. 025 ）. In addition, the amiloride-sensitive Na＋ currents in hyperoxia-exposed AT II cells were also increased （1 d：13.71 ±2.77 vs 8.92 ± 1.38,P 〈0.001;2 d：29. 12 ± 11.03 vs 10.41 ± 1.80,P 〈 0. 001 ）, which was consistent with the upregulated expression of β-ENaC and y-ENaC. However, the expression of a-ENaC was inhibited by hyperoxia to some extent （ 1 d ： 0. 31 ± 0. 05 vs 0. 46 ± 0. 05, P = 0. 025 ;2 d ：0. 30 ± 0.01 vs0.38±0.02,P=0.002;3d：0.37±0.06 vs 0. 37 ± 0. 08 , P = 0. 983 ） . Conclusion Hyperoxia enhanced the transport function of ENaC in neonatal rat AT II cells. Dysfunctional transport of Na＋ may not be a key factor involving in pulmonary edema at the early stage of bronchopulmonary dysplasia.

关 键 词：高氧 肺泡Ⅱ型上皮细胞 上皮钠通道 大鼠 新生 

分 类 号：R563[医药卫生—呼吸系统]