Objective    To investigate the effects of adenosine receptor A2a on the expression of epithelial sodium channel α-subunit (α-ENaC) in alveolar epithelium A549 cells and the effects of adenosine receptor A2a in acute lung injury/aute respiratory distress syndrome.     Methods    After alveolar epithelium A549 Cells were incubated with 0

0.1

1

10 and 100 μmol/L adenosine receptor A2a agonist CGS-21680 for 8 h or with 100 μmol/L CGS-21680 for 0

1

4

8

24 and 48 h respectively

the mRNA and protein levels of α-ENaC were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis respectively.     Results    After A549 cells were incubated with CGS-21680 at different doses for 8 h

the mRNA and protein levels of α-ENaC were elevated significantly at 0.1 μmol/L CGS-21680 treatment compared with the control group (P0.05)

and had a positive correlation with the increase of CGS-21680 concentration. After A549 cells were incubated with 100 μmol/L CGS-21680 for 4 h

the mRNA and protein levels of α-ENaC were elevated significantly compared with the control group (P0.05).     Conclusion    Activation of adenosine receptor A2a up-regulates α-ENaC

which is beneficial to the prognosis of acute lung injury/acute respiratory distress syndrome.