【摘要】 目的　观察不同浓度地塞米松 (DEX)诱导大鼠间充质干细胞 (MSCs)向成骨细胞分化。方法　采用原代MSCs体外培养技术 ,取大鼠后肢双侧股骨和胫骨骨髓 ,通过静置贴壁获取MSCs。以DEX、β 甘油磷酸钠和抗坏血酸作为诱导剂 ,测定诱导后细胞的MTT增殖率 ,碱性磷酸酶 (ALP)活性以及矿化结节形成能力。应用ALP染色法观察细胞形态 ,并在倒置相差显微镜下观察诱导过程中细胞形态的变化。结果　低浓度 (10 -8、10 -9、10 -10 mol/L)DEX诱导后的细胞形态由长梭形逐渐变为立方形 ,ALP表达明显升高 (P <0 .0 1)并且能够形成矿化结节 ;高浓度 (10 -6、10 -7mol/L)DEX明显抑制MSCs的增殖 (P <0 .0 1) ,抑制ALP表达 (P <0 .0 1) ,细胞形态由饱满的长梭形变为胞质宽大的扁平形 ,呈瘫痪状 ,且不能形成矿化结节。结论　低浓度DEX能够诱导大鼠MSCs向成骨细胞分化 ,而高浓度DEX抑制MSCs向成骨细胞的分化更多还原

【Abstract】 Purpose To induce mesenchymal stem cells(MSCs) to differentiate into osteoblats by dexa methasome(DEX). Methods The primary MSCs of the femurs and tibias of the rat were acquired through the characteristics that MSCs could adhere to the plastics while blood cells wouldn’t.The samples of MSCs were cultured with inducer of osteoblasts consisting of DEX,β?glycerophosphate and ascorbic acid.And the changes of MTT,alkaline phosphatase(ALP) were analyzed,ALP of the cells were stained in cell che mistry method,and mineralized bone nodules were stained with Alizarin red,at the same time the changes of cell morphology were observed through phase contrast microscope. Results After incubation with the lower doses of DEX,the morphology of MSCs changed from long spindle to cuboidal shape and expressed ALP significantly higher than that of control,more improtant,it could form mineralized nodules.While in the high doses of DEX,the cells showed a wide flat shape,decreased proliferation,and couldn’t form mineralied nodules. Conclusions DEX can induce MSCs to differentiate into osteoblasts in proper concentration,which implies MSCs are the progenitor of osteoblasts.更多还原