Micro-CT检测中等强度跑台运动对去卵巢大鼠腰椎微结构的影响

目的用micro-CT方法,评估中等强度跑台运动对去卵巢大鼠腰椎微结构的影响。方法将30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运动三个组。运动组每周进行4次45min、速度18 m/min、坡度5°的跑台训练。正式运动处理14周时,取第2腰椎检测骨密度,取第4腰椎行micro-CT分析及三维结构重建;取第3腰椎椎体进行椎体压缩实验。结果去卵巢运动组第2腰椎骨密度、第3腰椎最大载荷、最大应力和弹性模量以及第4腰椎骨小梁体积和骨小梁数目显著高于去卵巢静止组,骨小梁分离度显著低于去卵巢静止组,而骨小梁厚度无显著变化。结论中等强度跑台运动能改善去卵巢大鼠腰椎的微结构。

Effects of moderate-intensity treadmill exercise on bone microarchitecture in lumbar vertebrae of ovariectomized rats examined by micro-CT

Objective To investigate the effect of moderate-intensity treadmill exercise on microarchitecture of trabecular bone in ovariectomized （OVX） rats examined by micro-CT. Methods Thirty female 3-mnoth-old SD rats were randomly divided into following three groups ： sham-operation （ Sham ）, ovariectomized （ OVX ）, and ovariectomized and exercised （EX, 18 m/minute, 45 min/day, 5~ uphill, 4 times/week）. At 14＇h week of the regular exercise treatment, the bone mineral density （BMD） of lumbar vertebrae was detected by DEXA. Micro-CT scanning and three-dimensional struc- tural reconstruction were used to analyze the microarchitecture of the third lumbar vertebra and bone biomechanical test was carried out on the fourth lumbar vertebrae. Results Compared with the OVX group, the BMD of second lumbar vertebra, the maximum load, maximum stress, and elastic modulus in the third lumbar vertebra, as well as the volume and number of bone trabeculae in the fourth lumbar vertebra were significantly higher in the EX group whereas the trabecular separation was significantly lower. There were no significant differences in the thickness of trabeculae. Conclusion Moderate-inten- sity treadmill exercise may benefit the microarchitecture of lumbar vertebrae in ovariectomized rats.