Expression and transport function of epithelial sodium channel in alveolar epithelial type Ⅱ cells of hyperoxia-exposed neonatal rat
- Author:
- No author available
- Journal Title:
- Chinese Pediatric Emergency Medicine
- Issue:
- 5
- DOI:
- 10.3760/cma.j.issn.1673-4912.2012.05.016
- Key Word:
- 高氧;肺泡Ⅱ型上皮细胞;上皮钠通道;大鼠,新生;Hyperoxia;Alveolar epithelial type Ⅱ cells;Epithelial sodium channel;Rat,newborn
Abstract： Objective To investigate the effect of hyperoxia on the expression and transport function of epithelial sodium channel (ENaC) in neonatal rat alveolar epithelial type Ⅱ(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 using the whole-cell patch clamp technique.Results Hyperoxia upregulate the expression of β-ENaC and γ-ENaC subunits in the neonatal rat ATⅡ cells(β-ENaC:1 d:0.43 ±0.06 vs0.32 ±0.04,P =0.047;2 d: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;γ-ENaC:1 d:0.64±0.05 vs0.53 ±0.05,P =0.044;2 d:0.76 ±0.03 vs 0.52 ±0.04,P =0.001 ;3 d:0.77 ±0.06 vs 0.61 ±0.05,P =0.025).In addition,the amiloride-sensitive Na+ currents in hyperoxia-exposed AT Ⅱ cells were also increased (1d:13.71 ±2.77 vs8.92±1.38,P＜0.001;2d:29.12±11.03 vs 10.41 ±1.80,P＜0.001),which was consistent with the upregulated expression of β-ENaC and γ-ENaC.However,the expression of α-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.
- [1]张秋月,富建华,薛辛东.新生鼠肺泡Ⅱ型上皮细胞分离培养与鉴定[J].2010,25(6).
- [2]Maier L,Thome UH,Bischoff A,etc.Amiloride-sensitive nasal potential difference is not changed by estradiol and progesterone replacement but relates to BPD or death in a randomized trial on preterm infants.[J].2006,60(5).
- [3]Warner BB,Wispe JR,Stuart LA,etc.Functional and pathological effects of prolonged hyperoxia in neonatal mice.[J].1998,275(1 Pt.1).
- [4]Folkesson HG,Matthay MA,Clerici C.Lung epithelial fluid transport and the resolution of pulmonary edema.[J].2002,82(3).
- [5]Jackson RM.,Yue G.,Russell WJ.,etc.Increased Expression and Activity of Sodium Channels in Alveolar Type II Cells of Hyperoxic Rats[J].1995,92(18).
- [6]Couette S,Planes C,Clerici C,etc.Hypoxia and beta 2-agonists regulate cell surface expression of the epithelial sodium channel in native alveolar epithelial cells.[J].2002,277(49).
- [7]Thebaud B,Abman SH.Bronchopulmonary dysplasia: where have all the vessels gone? Roles of angiogenic growth factors in chronic lung disease.[J].2007,175(10).
- [8]Marcoux MO,Vanpee M,Gineste M,etc.Expression of water and ion transporters in tracheal aspirates from neonates with respiratory distress.[J].2009,98(11).
- [9]Chang JY,Hahn WH,Chang YS,etc.Recent trends in neonatal mortality in very low birth weight Korean infants: in comparison with Japan and the USA.[J].2011,26(4).
- [10]K, Richard,S J, Ramminger,L, Forsyth,etc.Thyroid hormone potentiates glucocorticoid-evoked airway Na+ transport without affecting alpha-ENaC transcription.[J].2004,576(3).
- [11]C M, Canessa,L, Schild,G, Buell,etc.Amiloride-sensitive epithelial Na+ channel is made of three homologous subunits.[J].1994,367(6462).
- [12]Tucker T,Su XF,Nie HG.Expression and regulation of epithelial Na+ channels by nucleotides in pleural mesothelial cells.[J].2009,40(5).
- [13]Shaw NJ,Southern KW,Vince G,etc.Electrical potential difference across the nasal epithelium is reduced in premature infants with chronic lung disease but is not associated with lower airway inflammation.[J].2007,61(1).
- [14]Wang Deng,Chang-Yi Li,Jin Tong,etc.Regulation of ENaC-mediated alveolar fluid clearance by insulin via PI3K/Akt pathway in LPS-induced acute lung injury[J].2012,13(1).
- [15]E, Hummler,P, Barker,J, Gatzy,etc.Early death due to defective neonatal lung liquid clearance in alpha-ENaC-deficient mice.[J].1996,12(3).