全身垂直振动对去卵巢骨质疏松大鼠松质骨微结构的影响

Effects of Whole-body Vertical Vibration on Trabecular Bone Microarchitecture of Ovariectomized Osteoporosis Rats

旨在观察全身垂直振动对去卵巢骨质疏松大鼠松质骨微结构的影响。将36只3月龄雌性SD大鼠按体重分层后随机分为假手术、去卵巢静止和去卵巢振动3个组。去卵巢10周时,去卵巢振动组大鼠开始在振动台上每天接受2次振动频率为90 Hz的振动刺激,每次15 min,每周7次。振动7周后,按解剖位置截取所有大鼠左股骨和第5腰椎,随机取6只大鼠的左股骨和第5腰椎进行micro-CT扫描及三维结构重建。选取股骨远端距生长板远端1 mm处,2.0 mm×3.5 mm,厚1 mm的骨组织以及腰椎生长板下1mm处,1.5 mm×4.0 mm,厚1 mm的骨组织为感兴趣区域,进行骨形态计量学分析。结果显示:去卵巢静止组股骨远端和第5腰椎体积骨密度(vBMD)、骨体积分数(BV/TV)、骨小梁数目(Tb.N)、骨小梁厚度(Tb.Th)显著低于假手术组,而骨小梁分离度(Tb.Sp)和结构模拟指数(SMI)显著高于假手术组;与去卵巢静止组比较,去卵巢振动组股骨vBMD、BV/TV和Tb.N显著增加,Tb.Sp显著下降,而Tb.Th和SMI差异无显著性。去卵巢振动组第5腰椎和去卵巢静止组所有检测指标差异均无显著性。以上结果表明,全身垂直振动能改善去卵巢骨质疏松大鼠股骨松质骨的微结构,但不能改善其腰椎松质骨的微结构。

The aim of this study was to investigate the effects of whole-body vertical vibration on trabecular bone mi- croarchitecture of ovariectomized osteoporosis rats. 36 healthy three-month old female SD rats were randomly divided into the following three groups by body weight： sham-operation （Sham）, ovariectomized （OVX）, and OVX whole- body vertical vibration （WBVV） groups. After ten weeks of OVX, the WBVV group rats were vibrated on a vibra- tion platform twice per day for 7 weeks according to the following schedule ： 90 hertz a minute and 15 min a time. At the end of 7 weeks vibration, the trabecular bone microarchitecture was detected by micro-CT in vitro. As revealed by the results of micro-CT, the volume bone mineral density （vBMD）, the fraction of bone tissues （BV/TV）, as well as the number of trabecular bone（Tb. N） and thickness of trabecular bone （Tb. Th） in both distal femur and the fifth lumbar vertebrae of OVX group were significantly lower than that of in the Sham group whereas the separa- tion of trabecular bone （ Tb. Sp） and the bone structure index （SMI） was significantly higher than that of in the sham group. The vBMD and the Tb. N in distal femur of the WBVV group was significantly higher than that of in OVX group while the Tb. Sp in WBVV group was significantly lower than that of in OVX group, however, there was no difference in the Tb. Th and SMI between the WBVV group and the OVX group. There were no difference in all detected parameters of the fifth lumbar vertebrae between the WBVV group and the OVX group. These results sug- gested that whole-body vertical vibration could improve the trabecular bone microarchitecture of femur in OVX osteo- porosis rats, but had no effects on the trabecular bone microarchitecture of lumbar vertebrae.