Effect of dexamethasone on the expression of aquaporin-1 in cultured rat pleural mesothelial cells

AIM:To study the effect of dexamethasone(Dex)on the expression of aquaporin-1(AQP-1)in cultured rat pleural mesothelial cells and to offer experimental support for the investigation of the mechanisms of pleural fluid treatment.METHODS:Rat pleural mesothelial cells were cultured in vitro.The expression of AQP-1 was detected by immunocytochemistry and reverse transcription-PCR(RT-PCR)after cells were identified,then the cells were treated with Dex for 24 hours at concentrations of 10-8,10-7,10-6,10-5 and 10-4mmol/L,and for 6 h,12 h,24 h,36 h,48 h,72 h at concentration of 10-4 mmol/L.Western blotting was used to analyze the expression of AQP-1 in cultured control and Dex-treated rat pleural mesothelial cells,and image analysis system to analyze the expression of AQP-1.RESULTS:Aquaporin-1 was expressed in cultured rat pleural mesothelial cells.The protein of AQP-1 expressed in rat pleural mesothelial cells was 755.04±19.81,843.72±19.41,862.96±26.53,694.80±32.00,938.08±13.32 in those treated with Dex at concentrations of 10-8,10-7,10-6,10-5 and 10-4 mmol/L,respectively,the levels was 2.02,2.26,2.31,1.86,2.52 fold higher than that in control group(372.90±16.46,P0.01).The protein of AQP-1 expressed was 554.14±23.57,917.78±38.62,1 587.20±61.22,1 322.09±28.65,918.40±26.62,1 117.60±51.32 in those treated with 10-4 mmol/L Dex after 6 h,12 h,24 h,36 h,48 h,72 h,the levels was 1.12,1.85,3.20,2.67,1.85 and 2.25 fold higher than that in control group(495.91±23.12,P0.01).CONCLUSION:The expression of AQP-1 in cultured rat pleural mesothelial cells is confirmed at the protein and mRNA level.Dex increases the expression of AQP-1 in a time-dependent manner.