雌激素对去卵巢大鼠骨丢失的骨形态计量学及组织学的影响

The Impacts of Sex Hormones on Histomorphometric and Histological Appearances of Bone in Ovariectomized Rats

目的了解大鼠卵巢性激素缺乏致骨丢失的组织学改变以及四种不同雌激素制剂对其的影响。方法将５０只ＳＤ大鼠随机分为６组，去势组（９只）在去势手术后３周处死大鼠；对照组（９只）开腹后关腹；去势＋利维爱组、去势＋盖福润组、去势＋倍美力组、去势＋维尼安组（各８只）在去势手术后３周予相应的药物治疗，术后６周（药物治疗后３周）处死各组大鼠，进行骨形态计量学、骨密度（ＢＭＤ）测定，并行病理及电镜下观察。结果（１）去势后３周大鼠骨量参数较对照组显著减少（Ｐ＜０．０５）；而骨小梁表面破骨细胞数、骨矿化沉积率、矿化缘长度较对照组显著增加（Ｐ＜０．０５）。去势后大鼠ＢＭＤ较对照组显著减少（Ｐ＜０．０１），骨小梁变细，骨的三维结构破坏。（２）各治疗组中，去势＋利维爱组和去势＋盖福润组骨吸收及转换参数中除骨矿化率仍减少外，其余参数与对照组相似（Ｐ＞０．０５）。去势＋倍美力组和去势＋维尼安组骨小梁的体积与去势组相似。ＢＭＤ在各治疗组均有增加，以去势＋利维爱和去势＋盖福润组增加较多（Ｐ＜０．０５）。结论（１）去势后大鼠骨丢失是由于卵巢分泌的性激素减少，破骨细胞活性增强，骨的力学强度降低所致。（２）卵巢切除后３周大鼠即出现高转换型快速骨丢失。?

Objectives To demonstrate the histomorphometric and histological changes of bone 3 weeks after bilateral ovariectomy in rats and to investigate the impacts of 4 different hormone replacement therapies on the bone histomorphometric, hostological appearances. Methods Bilateral ovariectomies were done on 41 female rats and sham operations on other 9 (sham group ) respectively . After 3 weeks , 4 different treatments : ie Livial , Gevrine , Premarin , Weinian were initiated separately on each 8 ovariectomized rats for another 3 weeks . The remaining 9 were served as controls (OVX group ) . All rats were sacrified either 3 weeks after ovariectomy / sham operation or at the end of hormone therapies . Their femoral bone mineral density (BMD) were measured by dual energy X-ray absorptiometry ( DEXA ) . Specimens of proximal femur were embedded undecacifide for histomorphometric analysis and of distal femoral metaphysics were procured for scanning electron miroscope (SEM) and pathologic examinations. Results (1) Three weeks after OVX , the femoral BMD, mean cortical thickness decreased significantly while the number of osteoclast increased significantly as compared with sham group. The trabecular became thinner and irregular which changed the bone microstructure in three dimension. (2) After treatment of 4 different preparations, the above parameters restored to various extents to the sham operation levels. Among them, there was greater increase of femoral BMD on the Livial and Gevrine group as compared with Premarin and Weinian group ( P <0.05). Conclusions Bilateral ovariectomy induced increased osteoclast activity and bone turnover , therefore caused accelerated bone loss. Treatment with combined sex hormones preparation could inhibit bone absorption and stimulate bone formation , especially those containing androgenic activity could increase the BMD.