中文摘要：

研究辐射对于Notch通路中重要的信号分子Notchl和Runx2，以及其对成骨细胞分化的影响。采用原代骨髓问充质干细胞诱导分化为成骨细胞，经过0、2和4Gy137Csγ射线照射后，采用实时定量PCR以及WesternBlot方法检测辐射对于Notchl、Runx2以及ALPmRNA和蛋白水平表达的影响。实验发现4Gy照射会导致NotchlmRNA（p〈O．05）和蛋白表达上调。2Gy和4Gy照射均能引起Runx2mRNA（p〈0．05）和蛋白表达水平上调，并导致ALPmRNA（p〈0．01）和蛋白水平表达的下调。研究表明：4Gy照射Notchl表达增高，导致ALP表达水平降低，对成骨细胞的分化产生了抑制，并且该抑制作用并没有受到Runx2表达水平上调的影响。在辐射影响下Runx2并不能对Notch信号通路发生抑制作用，从而解除其对成骨细胞分化的抑制作用。

英文摘要：

To investigate the radiation effect on Notch pathway in osteoblast and osteoblast differentiation, the expression of Notchl and Runx2 were analyzed. Osteoblast differentiated from Bone marrow stromal cells （BMSCs） was analyzed by real-time PCR and western blot after 2 Gy or 4 Gy 137Cs γ-irradiation. Notchl mRNA （p〈0.05） andprotein expression level were up-regulated after 4 Gy irradiation. 2 Gy and 4Gy irradiation increased Runx2 mRNA （p〈0.05） and protein expression level. ALP mRNA （p〈0.01） and protein expression level were repressed by 2 Gy and 4 Gy irradiation. These results indicated that up-regulated Notch 1 could inhibit osteoblast differentiation after irradia- tion of 4 Gy. Further more, up-regulated Runx2 expression did not repressed Notch signaling after irradiation of 4 Gy.