不对称性颌间牵引作用下BMP2在成年SD大鼠髁突关节下骨中的表达

目的：通过观察不对称牵引引起的成年大鼠髁突关节下骨中与骨改建密切相关的BMP2的表达情况,了解关节下骨对不对称机械应力的反应。方法：选用10周龄雄性SD大鼠220只（分轻力组104只、重力组104只、对照组12只）,实验组动物使用关节外固定加力装置,分别施加0.39N、1.18N（轻力组和重力组）,加力第28天拆除加力装置。在加力后3、7、14、28d以及停止牵引后3、7、14、28d分别取得左右侧标本,进行免疫组织化学染色,对结果进行计算机辅助的半定量分析。结果：正常的关节下骨也有BMP2的表达,内源性BMP2的表达增加与机械应力有关,BMP2表达的量受到力量的大小的影响。结论：BMP2参与不对称牵引引起的重塑过程。

Effect of Asymmetry Elastic Stretch on the Expression of BMP 2 in Adult Rat Condyle

Objective：To study the expression of BMP2 in the subchondral bone of mandibular condyle following asymmetric inter-maxillary elastic stretch.Methods：Two hundred and twenty 10-weeks-old SD rats were used in this study（one hundred and four rats loaded with 0.39N elastic force,another one hundred and four rats loaded with 1.18N elastic force,while twelve rats as control group）.The force-loading device was fixed on the right side by surgery.Half of the rats in experiment groups were killed after 3,7,14,28 days.The device was removed at the 28th day in the rest rats,and the rats were sacrificed after 31,35,42,56 days.The expression levels of BMP2 in all the joints were measured by immunohistochemistrial techniques.Results：The positive signal of BMP2 was presented in the normal subchondral bone,and the increase of inner BMP2 was related to the mechanic stimulation.The expression of BMP2 was influenced by extra mechanic loading.Conclusion：BMP2 takes part in the reconstruction process of asymmetry elastic stretch.