中文摘要：

目的：探讨持续压力对体外培养的大鼠成骨细胞内ERK1／2及GIT1蛋白相互关系及对大鼠成骨细胞迁移能力的影响。方法：取1-2天龄SD大鼠颅盖顶骨进行成骨细胞原代培养，采用压缩空气在密闭容器内对第2代细胞施以300kPa的静压力，分别于未加压，加压后0．5、1．0、2．0h提取细胞总蛋白，Western blot检测各组成骨细胞在Src抑制剂PP2不干预和干预下ERK1／2和GIT1的表达及其磷酸化，免疫共沉淀分析GIT1同活化的ERK1／2（phospho—ERK1／2，pERK1／2）相互作用的变化。Image—Pro Plus 5．0软件检测成骨细胞在Src抑制剂PP2不干预和干预下加压前后面积。结果：Westernblot结果显示DERKl／2和pGITl的表达在持续加压组较对照组明显增加；PP2干预下持续加压组的成骨细胞内的pERK1／2和pGIT1的表达较对照组无统计学差异；免疫共沉淀结果显示GIT1-pERK1／2结合力在持续加压组较对照组明显增加；持续加压后成骨细胞面积明显增加；PP2干预下持续加压后成骨细胞面积较对照组无统计学差异。结论：300kPa左右的持续性压力能通过激活Src的活性．从而诱导ERK1／2，GIT1的磷酸化，同时增加pERK1／2和GIT1的相互结合，促进大鼠成骨细胞的迁移，Src—GIT1／ERK1／2途径可能是成骨细胞力学信号转导过程中的重要通路之一。

英文摘要：

Objective：To investigate the role and mechanism of G-protein-coupled receptor kinase interacting protein 1 （GIT1）and extracellular signal-regulated kinases 1 and 2 （ERK1/2）in osteoblasts induced by durative pressure. Methods：The osteoblasts were mechanically stimulated on coverslips. The phosphorylation of ERK1/2 and GIT1 of osteobasts treated with or without the Src kinase inhibitor PP2 was measured by Western blot. The interaction between GIT1 and pERK1/2 was detected by coimmunoprecipitation. Cell area of groups treated with or without the Src kinase inhibitor PP2 was caculated by image-pro plus 5.0. Results：The phosphorylation of ERK1/2 and GIT1 and the interaction between GIT1 and pERK1/2 of osteoblasts treated with durative pressure significantly increased. The cell size increased significantly after durative pressure. Conclusion：These data suggests that 300 kPa durative pressure stimuates Src, consequently pathway induces the phosphorylation of ERKI/2 and GIT1 in osteoblasts, further increases the combination of pERK1/2 and GIT1 to migrate osteoblasts. The Src-GIT1/ERK1/2 pathway may play a important role in osteoblast migration induced by durative pressure.