模拟失重状态下雌、雄大鼠骨质疏松模型骨结构及生物力学对比研究  

A study on the changes of microstructure and mechanical properties in rat osteoporotic model under the simulated weightlessness condition

作　　者：张恒[1] 刘宁[2] 任宁涛 杨彦玲[3] 李洁[4] 雷伟[2] 张永刚[1] 张然[5] 崔赓[1] 

机构地区：[1]中国人民解放军总医院骨科,北京100853 [2]第四军医大学西京医院骨科,西安710032 [3]解放军第二炮兵总医院神经内科,北京100088 [4]中国人民解放军总医院妇产科,北京100853 [5]中国人民解放军总医院老年心血管研究所,北京100853

出　　处：《中国骨质疏松杂志》2015年第9期1076-1082,共7页Chinese Journal of Osteoporosis

摘　　要：目的模拟失重尾部悬吊雌、雌性大鼠模型松质骨骨密度、骨小梁结构、骨组织形态、骨代谢生化指标及力学性能的对比研究,为不同性别航天员飞行后骨量变化及航天医学提供实验依据。方法 3个月龄雌、雄性SD大鼠各20只,每组分别随机再分为2组,尾部悬吊4周组和空白对照组。到期处死SD大鼠,双能X线吸收法(dual-energy X-ray absorption DEXA)测定L4椎体、股骨踝部骨密度,Micro-CT进行骨小梁分析,改良丽春红染色方法进行骨组织切片染色,ELISA法检测血清骨代谢生化标志物,生物力学测试机进行生物力学检测。结果不同性别悬吊组大鼠较对照组大鼠椎体、股骨髁部骨密度均显著下降,松质骨的骨体积分数(BV/TV)、骨小梁厚度(Tb.Th)、骨小梁数目(TB.N)、表面积体积比(BS/BV)较对照组显著降低(P<0.05),骨小梁间隙(TB、Sp)较对照组显著增加;骨代谢生化指标骨特异性碱性磷酸酶(BALP)、抗酒石酸酸性磷酸酶(TRAP)悬吊组较对照组显著增加,雄性悬吊组分别为对照组的4.1和2.7倍,雌性悬吊组分别为对照组的4.5和3.1倍;生物力学测试表明悬吊组椎体的最大压缩载荷(N)、最大压缩压力(MPa)、股骨最大抗弯曲载荷(N)雄性悬吊组分别较对照组下降:27.5%、26.4%、24.8%;雌性悬吊组分别较对照组下降:36.6%、33%、34%,力学强度显著下降。通过雌、雄性悬吊大鼠对比研究发现,雌性大鼠L4椎体、股骨髁部BMD,松质骨BV/TV、Tb.Th、TB.N、TB.N以及椎体的最大压缩载荷(N)、最大压缩压力(MPa)、股骨最大抗弯曲载荷(N)显著降低(P<0.05),骨小梁间隙(TB、Sp)、BALP、TRAP雌性悬吊组较雄性悬吊组显著增加(P<0.05)。结论尾部悬吊雌、雄性大鼠4周后分别出现明显的骨质疏松、骨小梁三维结构破坏、椎体及股骨生物力学显著下降、骨代谢失平衡,理论上增加了骨折的风险。同时更值得注意的是雌性悬吊大鼠骨质疏松程度较雄性�Objective By analyzing the changes of bone microstructure, biochemical metabolism and mechanical properties of male and female rats in a tail-suspending osteoporosis model simulating weightlessness, to provide experimental evidence for bone mass change of astronauts and aerospace medicine. Methods Twenty male and 20 female 3 - month-old SD rats were selected and randomly divided into 2 groups, tail-suspending （TS） model group and control group. After 4 - week experiment, the rats were killed. Bone mineral density （BMD） of L4 lumbar vertebrae and the femurs was measured using dual-energy X-ray absorptiometry （DEXA）. The trabeculae were analyzed using micro-CT. Ponceau staining was used for the bone tissue slices. Bone biochemical markers were detected using ELISA method. The biomechanical indexes were tested using a biomechanical testing machine. Results The BMD of L4 and the femurs in the TS groups was obviously lower than that in control groups, The bone volume fraction （BV/TV）, the thickness （Tb. Th） and number of the trabeculae （TB. N） of were also lower （P 〈0.05）. However, the bone surface to bone volume （BS/BV） and trabecular separation （Tb. Sp） in TS group were significantly higher than those in control group （ P 〈 0. 05 ）. The bone metabolic biochemical markers BLAP and TRAP in the TS groups were remarkably higher than those in control groups, which were 4. 1 and 2.7 times in male groups and 4.5 and 3. 1 times in female groups, respectively. Biomechanical testing showed that the maximum compressive load （N） , maximal compressive stress （MPs） of lumbar vertebrae, flexural load of the femurs decreased in male TS group by 27.5% , 26.4% , and 24.8% , respectively, and in female TS group by 36.6% , 33% , and 34% , respectively, comparing to the control group. BMD of L4 and the femurs, BV/TV, Tb. Th, TB. N, N, and MPa in female TS groups decreased significantly comparing to those in male TS groups. BALP and TRAP increased significantly in male TS groups compari

关 键 词：模拟失重 骨质疏松 SD大鼠 MICRO-CT 生化标志物 生物力学 

分 类 号：R852.22[医药卫生—航空、航天与航海医学]