骨折端微动对骨形态发生蛋白-2表达的影响

The effect of micromovement of fracture ends on the expression of bone morphogenetic protein-2

目的 研究骨折端微动时轴向应力对骨形态发生蛋白-2（BMP-2）表达的影响。方法 72只新西兰大白兔分为微动组与固定组，利用免疫组化及原位杂交方法检测两组动物骨折端BMP-2蛋白及mRNA表达的不同。结果 BMP-2蛋白及mRNA表达于间质细胞、成骨细胞、成软骨细胞、骨细胞及骨基质。在骨折愈合过程早期高度表达，峰值位于骨折后14d，其后表达水平降低。BMP-2蛋白及mRNA染色阳性指数术后14、21、28d微动组大于固定组，差异有统计学意义（P〈0．05）。结论 骨折端微动时BMP- 2蛋白及mRNA表达在特定时间增强。

Objective To study the effect of micromovement of fracture ends on the expression of bone morphogenetic protein-2 （BMP-2） . Methods Fracture models of mid tibia were created in 72 rabbits which were randomly divided into 2 groups of equal size, a micromovement group and a fixation group. After anatomic reduction, the fracture was fixated in the fixation group. In the micromovement group, after fixation, an axial movement of 0. 5mm was allowed on the middle rod of the external fixator. The expressions and positive indexes of BMP-2 and its mRNA were quantitatively detected by immunology histochemistry （IHC） and in situ hybridization （ISH） . Results BMP-2 and BMP-2 mRNA were expressed in mesenchymal cells, osteocytes, bone matrix, osteoblasts and chondroblasts. The expression peak was at 14 d, and weakened gradually. The positive indexes of BMP-2 and BMP-2 mRNA in the micromovement group were higher than those in the fixation group at 14, 21, and 28 days, with statistically significant difference between the 2 groups （ P 〈 0. 05） . Conclusion Micromovement at the fracture ends can up-regulate the expression of BMP-2.