大鼠卵巢切除后松质骨骨丢失的扫描电镜观察

Scanning telescope observation of cancellous bone loss of ovariectomized rats

目的 :采用扫描电镜观察大鼠卵巢切除后松质骨表面骨吸收情况及其与生物力学强度改变之间的关系。方法 :6月龄SD大鼠卵巢切除后 3个月 ,取出左胫骨上段 ,采用JEOLJSM -840扫描电镜观察松质骨表面骨吸收陷窝的数量、分布 ,胶原的排列、分布 ,骨小梁的穿孔、中断等情况。取出右股骨上段 ,在万能材料试验机上进行力学强度测定。结果 :正常大鼠胫骨上段松质骨丰富 ,骨小梁表现光滑 ,胶原排列有序。卵巢切除后则松质骨减少 ,表面吸收陷窝增多、增深 ,吸收陷窝内胶原排列紊乱 ,游离末端常见。板状骨小梁的骨吸收有扩大倾向 ,棒状小梁则变细、中断 ,拱状小梁顶部也常见骨吸收活动 ,力学测试结果表明 ,卵巢切除后大鼠胫骨上段的生物力学强度显著下降。结论 :大鼠卵巢切除后松质骨表面骨吸收明显活跃 。

Objective: Scanning telescope was used to observe bone resorption carried out on the surface of cancellous bone and it's relationship with the change of biomechanical strength of the cancellous bone.Methods: 6 months-old SD rats were ovariectomized and the left tibias were obtained after 3 months.JEOL JSM 840 scanning telescope was used to observe the resorption pits on the surface of cancellous bone and colagen distribution on the bottom of the pits.The right tibias were also obtained to measure the biomechanical strength of its' upper end.Results: Cancellous bone was rich inside the upper tibias of the normal rats,the surface of the bone was smooth and collagen distribution was in order.Cancellous bone decreased after ovariectomy,resorption pits increased and deepened,collagen in the bot tom of the pits was distributed irregularly.Resorption pits could also be seen at the top of the arched trabecula.The biomechanical strength of the upper tibias was decreased obviously after ovariectomy.Conclusion: Ovariectomy enchances bone resorption on the surface of cancellus of the rats,especially the resorption carried out at the top of arched trabecula affects the cancellous bone strength mostly.