Akhter M P, Otero J K, Iwaniec U T, Cullen D M, Haynatzki G R, Recker R R
Osteoporosis Research Center, Creighton University, Omaha, NE 68131, USA.
J Musculoskelet Neuronal Interact. 2004 Mar;4(1):33-40.
This study assessed mouse strain-related differences in vertebral biomechanics and histomorphometry in inbred mice strains shown to differ in bone mineral content (BMC) and areal density (BMD) (as measured by pDEXA). Lumbar vertebrae L3 to L5 were collected from three mice strains (C3H/HeJ[C3], C57BL/6J[B6], and DBA/2J[D2], n=12/strain, 4-month-old female, 22.2 +/- 0.3g). BMC and BMD were measured in L3 and L4 using peripheral dual energy x-ray absorptiometry. The L4 vertebral body was then mechanically tested in compression to determine structural properties (ultimate/yield load, stiffness) from load-displacement curves and derive apparent material properties (ultimate/yield stress, and modulus of elasticity). L5 was processed for histomorphometric evaluation. Vertebral BMC and BMD were greater in C3 than in B6 and D2 mice. Vertebral trabecular/cancellous bone volume was smaller in C3 than in D2 and B6 mice. Trabecular bone formation rates were greater in D2 than in B6 and C3 mice. Osteoid surface was smaller in C3 mice than in B6 and D2 mice. Differences in osteoclast and mineralizing surfaces were not detected among the three mouse strains. In addition, there were no significant differences in biomechanical properties between the three strains. Despite the greatest BMC and areal BMD in C3 mice, the lack of strain-related differences in vertebral body strength data suggests that the biomechanical properties may be affected by the bone distribution and/or complex combination of cortical and cancellous bone at this site.
本研究评估了近交系小鼠品系中与椎体生物力学和组织形态计量学相关的差异，这些品系在骨矿物质含量（BMC）和面积密度（BMD）（通过外周双能X线吸收法测量）方面存在差异。从三种小鼠品系（C3H/HeJ[C3]、C57BL/6J[B6]和DBA/2J[D2]，每个品系n = 12只，4月龄雌性，体重22.2±0.3g）收集腰椎L3至L5。使用外周双能X线吸收法测量L3和L4的BMC和BMD。然后对L4椎体进行压缩力学测试，根据载荷-位移曲线确定结构特性（极限/屈服载荷、刚度），并得出表观材料特性（极限/屈服应力和弹性模量）。对L5进行组织形态计量学评估。C3小鼠的椎体BMC和BMD高于B6和D2小鼠。C3小鼠的椎骨小梁/松质骨体积小于D2和B6小鼠。D2小鼠的小梁骨形成率高于B6和C3小鼠。C3小鼠的类骨质表面小于B6和D2小鼠。在三种小鼠品系中未检测到破骨细胞和矿化表面的差异。此外，三种品系之间的生物力学特性没有显著差异。尽管C3小鼠的BMC和面积BMD最大，但椎体强度数据缺乏品系相关差异表明，生物力学特性可能受该部位骨分布和/或皮质骨与松质骨的复杂组合影响。
