卵巢切除后大鼠骨小梁重建过程的电镜观察

Electro-microscopic observation of trabecular bone remodeling in ovariectomized rats

目的 :建立大鼠卵巢切除后骨质疏松模型 ,观察在卵巢切除诱发骨质疏松条件下骨小梁重建的电镜变化 ,分析骨小梁节点数减少而游离末端数增加的原因。方法 :3月龄雌性Wistar大鼠 36只 ,分4、8、12周组 ,每组分OVX(卵巢切除组 )和SHAM(假手术组 )两小组。用扫描电镜、透射电镜对胫骨近干骺端骨小梁的微结构进行观察。结果 :①骨小梁骨重建活动分布于骨小梁微构筑各个部位 ,但以St、Nd St区最显著 ;②OVX后骨小梁穿孔、断裂多见于水平骨小梁 ,骨小梁网状结构 4周时完整 ,第 8周和第 12周后逐渐被破坏 ,12周最严重 ;OVX后骨小梁表面的胶原纤维逐渐变得杂乱、稀薄。结论 :OVX后St、Nd St区骨重建最活跃 。

Objective:[Using ovariectomized rats as a osteoporosis models to observe the trabecular remodeling process under the electron microscope,to explore the cause that decreased in the number of trabecular nodes and increased in the number of free ends.Methods:[Thirty six (3 month old) female Wistar rats were divided equally into ovariectomized (OVX) and shame operated (SHAM) groups.Each groups were sacrificed at 4,8 and 12 weeks respectively.Scanning and transmission electron microscope were used to observe the changes of proximal tibia trabecular microarchitecture.Results:[①Bone remodeling process was distributed in every region on the surface of trabecular microarchitecture where the St and Nd St region were most significantly.②In OVX groups,the trabecular net work were disrupted gradually from 8 to 12 weeks but almost intact in 4 weeks.The transverse trabecular was easier to be turned into thinner,perforated and broken;the collagen was turned into scrappy,disorder and thinner.Conclusion:[The bone remodeling activity are increased significantly in the St and Nd St region of trabecular microarchitecture than other region after OVX.This may be the cause that decreasing the number of trabecular nodes and increasing the number of free ends. [