【摘要】 观察激素诱导骨髓基质细胞分化成脂肪细胞的作用，揭示激素性股骨头缺血性坏死的病理学机制。方法　采用原代骨髓基质细胞体外培养技术，取小鼠双侧股骨骨髓细胞，通过细胞贴壁、分离获取骨髓基质细胞。以地塞米松作为脂肪细胞分化诱导剂处理细胞，苏丹Ⅲ染色，光镜下脂肪细胞计数。结果以递增浓度（０、１× １０~－９、１× １０~－８、１× １０~－７、１× １０~－６ ｍｏｌ／Ｌ）地塞米松处理细胞并培养 ２１天后， １×１０~－６ ｍｏｌ／Ｌ组中诱导分化生成的脂肪细胞最多，对照组中脂肪细胞最少，各组脂肪细胞随地塞米松浓度增大而增多，具有一定的剂量依赖性。实验组细胞经高浓度（１×１０~－７ ｍｏｌ／Ｌ）地塞米松处理并培养１２天后，其细胞内碱性磷酸酶活性明显低于对照组，两者差异有非常显著性意义（Ｐ＜０．０１）。结论　地塞米松能够直接诱导骨髓基质细胞大量分化成脂肪细胞，其成骨分化减少，这可能是大剂量应用激素后股骨头骨髓内脂肪组织增多，骨内压升高，导致骨微循环障碍，同时骨修复过程缓慢，从而发生股骨头缺血性坏死的原因。更多还原

【Abstract】 Objective To observe steroid-induced marrow stromal cell differentiation into adipocytes to elucidate the pathogenesis of the steroid-induced avascular necrosis of the femoral head. Methods The primary marrow stromal cells of the femur of the mouse were procured and cultured. The samples were isolated; after adherent growth culture in vitro, and were treated with dexamethasone which acted as adipocyte differ- entiation inducer. The cells in culture were stained with Sudan Ⅲ. The number of adipocytes were counted on a light microscope. Results After the cells in culture were treated with increasing(0, 1 × 10~-9, 1 × 10~-8, 1 × 10~-7, and 1 × 10~-6 mol/L) concentrations of dexamethasone for 21 days, the number of adipocytes, which was highest in 1 ×10~- 6 mol/L groups and lowest in the control, increased with higher concentrations of dexamethasone and showed a dose-dependent relation. Alkaline phosphatase activity in the cells exposed to higher concentration of dexamethasone(1 × 10~-7 mol/L) for 12 days was significantly lower than that in the control (P < 0. 01 ). Conclusion Dexamethasone can directly induce marrow stromal cell differentiation into a large number of adipocytes and inhibit osteogenic differentiation. This might lead to an increase in marrow fat volume of the femoral head following administration of high dose of steroids; eventually an increase of intraosseous pressure occurred, with a decrease of vascular perfusion. Without sufficient repair of the necrotic bone, the final result is avascular necrosis of the femoral head.更多还原