去卵巢对大鼠骨密度的影响

Effect of ovariectomy on bone mineral density in rats

目的 探讨去卵巢对大鼠骨密度 (BMD)的影响。方法 2 0只 3 5月龄SD雌性大鼠分别摘除双侧卵巢 (OVX)或假性去卵巢 (Sham) ,术后 14周处死 ,应用QDR - 4 5 0 0A型扇形束双能X射线吸收法 (DXA)测量大鼠全身、离体股骨、胫骨、腰椎及其兴趣区的BMD。结果 ①术后 6周OVX组全身BMD显著低于Sham组 (P =0 0 4 8) ,术后 14周两组间无显著差异 ;②术后 14周OVX组离体股骨BMD显著低于Sham组 (P <0 0 0 1) ,股骨远侧干骺端平均降低 11 6 % (P <0 0 0 1) ;③术后 14周右侧离体胫骨BMD两组间差异无显著性 ,但OVX组胫骨近侧干骺端BMD显著低于Sham组 (P <0 0 0 1) ;④术后 14周OVX组腰椎 (L4 -L6 )的BMD显著低于Sham组 (P =0 0 14 ) ,第六腰椎降低明显 ,平均降低 8 1% (P =0 0 0 5 )。

Objective\ To investigate the effect of estrogen deficiency on bone mineral density(BMD)in rats. Methods\ Twenty SD rats,3.5 month old,were surgically ovariectomized (OVX) or sham operated(Sham).The rats were sacrificed at 14 weeks post surgery.Whole body BMD,the BMD of femur,tibia and lumbar spine in vitro and the BMD of their regions of interest were all measured by dual energy X ray absorptiometry(DXA)using QDR 4500A equipment. Results\ ①Whole body BMD in OVX at 6 weeks post surgery was significantly lower than that in sham controls( P =0 048),but there was no significant difference between OVX rats and sham controls at 14 weeks post surgery.②The femoral BMD in vitro was markedly decreased in OVX rats at 14 weeks post surgery,compared to that in sham operated rats( P <0 001),especially for the distal femoral metaphysis( P <0 001,-11 6%).③There was no significant difference at 14 weeks post surgery for tibial BMD in vitro between OVX rats and sham controls,but the BMD of proximal tibial metaphysis in OVX rats was significantly decreased,compared to that in sham operated rats( P <0 001).④The BMD of lumbar spine(L 4-L 6) in OVX rats was significantly lower at 14 weeks post operation than that in sham controls( P =0 014),especially for the sixth lumbar vertebra( P <0 005,-8 1%). Conclusion The regions of interest which are rich in trabecular bone are the sites affected most markedly by ovariectomy.