中文摘要：

目的探讨地塞米松对猪骨髓间充质干细胞（MSCs）凋亡的影响。方法体外分离猪MSCs，培养扩增后，培养基中分别加入浓度为0,1×10^-8，1×10^-7，1×10^-6mol／L地塞米松，培养24h后，Hoechst 33258染色，AnnexinV—FITC／PI双染流式细胞术分析不同浓度地塞米松对MSCs凋亡的影响。结果Hoechst 33258染色可见：1×10^-6mol／L地塞米松诱导后MSCs部分细胞核与细胞质中可见浓染致密的颗粒荧光。流式细胞术检测显示各实验组细胞凋亡率较对照组高，尤其以浓度为1×10^-6mol／L最显著。结论地塞米松可引起MSCs凋亡，有浓度依赖性，1×10^-6mol／L引起MSCs凋亡最为显著。

英文摘要：

Objective To study the effects of dexamethasone on the apoptosis of pig mesenchymal stem ceils. Methods Pig MSCs were isolated from bone marrow and grown in vitro. At 24 hours after dexamethasone （0,1 1×10^-8 ,1 1×10^-7, 1 1×10^-6 mol/L）induced, a Hoechst 33258 stain and Annexin V-FITC/PI flow cytometry examinations were carried out to detect the apoptosis of MSCs. Results With 10^-6 mol/L dexamethasone used to cell incubation for 24 h, the MSCs showed the morphological characteristics of apoptosis. The analysis of Annexin V-FITC/PI flow cytometry showed that the MSCs apoptosis rates at different concentration （11×10^-8, 1 1×10^-7,1 1×10^-6 mol/L） were significantly higher in dexamethasone treated group than in control group. The peak rate of apoptosis was in 1 1×10^-6 mol/L dexamethasone treated group. Conclusions Dexamethasone could induce mesenchymal stem cells apoptosis by dose-dependent.