大鼠去卵巢后不同时期骨微结构和力学性能的变化特征  

Longitudinal changes of bone microstructure and biomechanical properties of vertebral trabeculae in OVX rats

作　　者：马育林[1] 戴如春[2] 盛志峰[2] 张玉海[3] 金艳[2] 廖二元[2] 

机构地区：[1]南方医科大学附属小榄人民医院内分泌科,广东中山528415 [2]中南大学湘雅二医院代谢内分泌研究所,长沙410011 [3]海南省人民医院内分泌科,海口570208

出　　处：《中华骨质疏松和骨矿盐疾病杂志》2009年第1期28-35,共8页Chinese Journal Of Osteoporosis And Bone Mineral Research

基　　金：国家自然科学基金资助项目(30400514);湖南省自然科学基金(06JJ50029);卫生部临床学科重点建设资助项目(2004-468-50)

摘　　要：目的 揭示大鼠在去卵巢后不同时期腰椎松质骨微结构退变的变化特征,探讨骨整体力学性能下降的同时可能存在的各种适应性代偿性变化。方法 50只7月龄SD大鼠随机分为基线、去卵巢组(OVX组)和假手术组(SHAM)。基线组10只,其余每组均20只。实验开始时先将基线组10只处死,OVX组和SHAM组分别在手术后3周、15周各处死10只,留取动脉血清及腰椎标本,骨微结构、力学和生化指标的测定。结果去卵巢后3周时OVX组表观骨密度、骨体积分数、骨小梁厚度和骨小梁数量均较SHAM和基线降低(P<0.05),各向异性度较基线下降(P<0.05)而与SHAM组无统计学差异。骨小梁面积密度、骨小梁间隔和结构模型指数均较SHAM和基线组增加(P<0.05)。去卵巢后3周时OVX组最大应力、弹性模量、血清TRAP-5b和骨细胞密度均低于基线(P<0.05)而与SHAM组无统计学差异。去卵巢后15周时OVX组表观骨密度、骨体积分数、骨小梁数量和联接密度、最大应力、TRAP-5b和骨细胞密度均较SHAM和基线组降低(p<0.05),骨小梁结构模型指数、骨小梁间隔和各向异性度均较SHAM和基线组增加(P<0.05),骨小梁面积密度和厚度均与SHAM和基线组无统计学差异。结论大鼠去卵巢后腰椎骨量快速丢失,骨微结构逐渐退变,而血清TRAP-5b水平下降及骨细胞密度、骨小梁各向异性度和厚度的适应性增加,可能在一定程度上代偿骨力学性能的下降,有利于维持骨结构的完整性。Objective To characterize the longitudinal changes of cancellous bone microstructural deterioration of vertebral trabeculae and to investigate the possible adaptative compensations in OVX rats. Methods 50 Female Spra- gue-Dawley rats of seven-month-old were ovariectomized （OVX）, SHAM-operated （SHAM） or left unoperated （baseline control）. The vertebral bodies and artery blood samples were harvested at baseline, 3 and 15 weeks postoperatively. The compressive test was performed on L5 vertebral body, and micro-computed tomography （μ-CT） assessment was performed to estimate 3D bone mineral density （BMD） and microstructure parameters of the L6 vertebral body. After fatigue damage testing, L6 vertebral body was bulk-stained in 1% basic fuchsin and embedded in methylmethacrylate. Mounted bone slices were used to measure osteocyte density （Ot. N/T. Ar）. Blood samples were used to analyze serum tartrate-resistant acid phosphatase 5b （TRAP-5b）. Results At 3 weeks postoperatively, apparent BMD, trabecular volume fraction （TV/ BV）, trabecular thickness （Tb. Th）, trabecular number （Tb. N ）, tartrate-resistant acid phosphatase 5b （TRAP-5b）, maximum load （ML）, elastic modulus （EM） and osteocyte density （Ot. N/T. Ar） were significantly decreased in OVX rats than those of SHAM and baseline control rats. Degree of anisotropy （DA） was significantly decreased in OVX rat than those of baseline control group. Bone area density （BS/BV）, trabecular separation （Tb. Sp） and trabecular model index （SMI） were significantly increased in OVX rat than those of SHAM and baseline control rats. There were no significant differences between OVX and SHAM ratswith regard to DA, trabecular connectivity density （Conn. D）, ML, EM, Ot. N/ T. Ar and TRAP-5b. There was no significant difference with regard to Conn. D between OVX and baseline control rats. At 15 weeks postoperatively, apparent BMD, TV/BV, Conn. D, Tb. N, TRAP-5b, ML and Ot. N/T. Ar were significantly decreased in

关 键 词：骨微结构 骨细胞密度 生物力学 去卵巢大鼠 抗酒石酸酸性磷酸酶5B 

分 类 号：R318.01[医药卫生—生物医学工程] R681[医药卫生—基础医学]