增龄性变化对大鼠骨质量、血清骨代谢指标影响研究

目的]探讨增龄性变化对大鼠骨质量、血清骨代谢指标的影响。方法]14只新生雄性Sprague Dawley（SD）大鼠，同等条件下饲养，饲养至6个月按体重随机分为老龄骨质疏松组（AO组）和青年对照组（YC组），将YC组安乐处死，AO组继续饲养至22个月，两组大鼠均取左侧股骨，测量骨密度、骨组织形态计量学指标，以及骨矿水平及骨代谢指标。结果]腰椎及股骨密度（BMD）在老龄大鼠均下降，其中股骨密度下降尤其显著（P〈0.01）。与YC组比较，AO组大鼠骨钙素水平显著降低（P〈0.01），抗酒石酸酸性磷酸酶（TRACP）水平显著升高（P〈0.05）；骨生物力学测定发现，AO组大鼠的股骨最大受力负荷下降。骨形态计量学测定发现，AO组大鼠骨小梁体积、骨小梁宽度、骨皮质厚度显著下降（P〈0.05或P〈0.01），骨小梁间隙增大（P〈0.01），AO组大鼠骨小梁普遍变薄、变细甚至断裂穿孔。结论]22月龄雄性大鼠发生了骨质疏松的变化，骨形成降低，骨矿含量下降，骨微观组织结构破坏。

A study on effect of age- augmented changes in bone quality and serum bone metabolism indexes of rats

Objective： To discuss the effect of age--augmented changes on bone quality and serum bone metabolism indexes in rats. Methods： A total of 14 Sprague Dawley （SD） male rats had been selected and had been kept under the same conditions. All rats were divided into two groups randomly after six months＇ breed according to their body weight, that was aged osteoporosis group （AO） and youth control group （YC）. YC group rats were fed and sacrificed happily. AO group rats had been fed for 22 months. The left femur of all rats were taken and bone densi- ty, bone histomorphometry indexes, bone mineral level and bone metabolism indexes of the left femur had been measured. Results： Both lumbar and femur bone mineral density （BMD） in aged rats were lowered. Among the total,femur density was especially lowered （P〈0.01）. The osteocalcin level of AO group were notably decreased compared with that of YC group （P〈0.01）. TRACP level of AO group rats was notably elevated （P〈0.05）. Bone biomechanics showed that the maximum load of the femur of AO group rats was decreased. Bone histomorphometry showed that bone trabecula bulk, bone trabecula extent and cortical thickness bone of AO group rats were conspicuously lowered （P〈0.05 or P〈0.01）. The interspaces of bone trabecula of AO group rats were increased （P〈0.01）. Bone trabecula of aged group rats were universally thinned and even disrupted and perforated. Conclusion： The osteoporo- ses had occurred in 22 - months old male rats. Bone formation of them was degraded. Bone mineral content of 22 - months old rats had decreased and bone microstructure had been damaged.