辐射对骨髓间充质干细胞增殖分化及相关基因表达的影响

为观察大鼠局部大剂量辐射后，骨髓间充质干细胞增殖分化及相关基因的表达，以^137Csγ射线对大鼠股骨头部位局部照射，吸收剂量为30Gy，剂量率为0．83Gy／min，照后两周取股骨头进行骨髓间充质干细胞（BMSCs）培养，四甲基偶氮唑盐比色法（MTT）绘制生长曲线及进行集落计数，RT-PCR检测Cbf-α1，PPAR-γ，VEGF—a和KDR的表达。骨髓间充质干细胞大剂量辐射后细胞增殖能力明显降低，集落形成数目减少；Cbf-α1，PPAR-γ，VEGF—a和KDR的表达均降低，其中Cbf-α1，PPAR-γ，VEGF—a表达降低幅度分别达18．98％，9．46％和57．34％，与对照组相比差异显著（p〈0．05）。故体外大剂量局部辐射明显损伤骨髓间充质干细胞，使其增殖分化及相关基因的表达降低。

Radiation effect on the generation and expression of bone marrow stromal cells

In order to investigate focal flushing dose radiation effect on the generation, differentiation and gene expression of bone marrow stromal cells the femoral head of rats was irradiated at 30 Gy by ^137Cs γ-rays （dose rate： 0.83 Gy/min）. Then the bone marrow stromal cells （BMSCs） was cultured. The ability of proliferation and colony formation was observed and the expression level of Cbf-α1, PPAR-γ, VEGF-a and KDR was detected by RT-PCR technology in two weeks later. It has been found that after partly irradiated by ^137Cs γ-rays the proliferation and the number of colony of BMSCs in irradiated group decreases obviously meanwhile the expression level of Cbf-α1, PPAR-γ and VEGF-a in irradiated BMSCs obviously decreases by 18.98 %, 9.46 %, 57.34 % and 5.56 % respectively compared to the normal BMSCs （p〈0.05）. It shows that the focal great radiation could damage the BMSCs and depress the generation, diferentiafion and the expression of the related genes obviously.