Mechanism of growth hormone inhibiting of alveolar type Ⅱ epithelial cells in rats / 中华急诊医学杂志

ABSTRACT

Objective To investigate the mechanism of growth hormone inhibiting IPS-induced apoptosis of alveolar type Ⅱ epithelial cells in rats. Method Isolated and purified AEC Ⅱ cells of SD rats were divided into 5 groups,8 duplicate wells in each group. Group I served as control group; group ⅡLPS 10 ug/ml;group ⅢLPS 10 ug/ml + GH 50 ng/ml;gronp IVLPS 10 ug/ml + GH 100ng/ml; group V LPS 10 ug/ml + GH 200 ng/ml. LPS was finally added into wells in group Ⅱ～V . After the cells were incubated for 24 hours, the apoptosis rate and necrosis rate of AEC Ⅱ cells stained with Annexin V/PI were detected by flow cytometry and Fas protein of AEC Ⅱ cells were measured by immunocytochemistry. Results (1) The apoptosis rate and necrosis rate of AECⅡ cells in group Ⅱ,Ⅲ, Ⅳ and V were significantly hitOer than those in group Ⅰ( qapoptosis rate Ⅰ, Ⅱ =12.26,qnecroeis Ⅰ,Ⅱ=18.34, qapoptosisⅠ.Ⅱ=9.63,qnecrosisⅠ,nⅡ=5.75,qapotosisⅠ,Ⅳ= 9.15,qnecrosisⅠ,Ⅳ= 5.39, qapotosisⅠ,Ⅴ = 10.87, qnecrosisⅠ,Ⅴ = 5.91, P 0.05), but lower in group Ⅲ,IV and V than those in group Ⅱ(qapoptosis Ⅱ,Ⅲ= 15.24, qpecrosisⅡ,Ⅲ=16.38, qapoptosisⅡ.Ⅳ = 15.95,qnecrosisⅡ.Ⅳ=16.95, qapoptosis rate Ⅱ,Ⅴ=14.57, qnecrosisⅡ.Ⅴ = 15.61,P<0.05). (2)The positive rate of Fas expression on AEC Ⅱ cells in group Ⅱ,Ⅲ, Ⅳ and V was obviously higher than that in group Ⅰ. ( q Ⅰ.Ⅱ=35.67, qⅠ ,Ⅲ=14.32, qⅠ,Ⅳ = 13.87, qⅠ.Ⅴ=26.16, P<0.05), but lower in gronpⅢ ,Ⅳ and Ⅴ than that in gronp Ⅱ(qⅡ,Ⅲ=12.54, qⅡ,Ⅳ = 13.02, qⅡ,Ⅴ =6.96, P<0.05). Conclusions GH can probably de-crease the apoptosis of AEC Ⅱ cells by inhibiting Fas expression.