【作者】 谢金珍；

【导师】 卜淑敏；

【作者基本信息】 首都体育学院 ， 运动人体科学， 2011， 硕士

【摘要】 实验目的:绝经后骨质疏松症是女性绝经后常见的一种疾病。本研究采用去卵巢大鼠模型模拟女性绝经后骨质疏松状况,探讨中等强度跑台运动减缓去卵巢大鼠骨量丢失的作用机制。实验方法:将60只3月龄雌性SD大鼠按体重随机分为假手术、去卵巢静止和去卵巢运动三个组。手术后第2周,去卵巢运动组大鼠先在小动物跑台上开始适应训练1周,然后每周进行4次/45min、速度18m/min、坡度5°的跑台训练。正式运动训练15周后,将每组大鼠按体重又随机分为两个亚组,分别在去卵巢16和32周,称量各组大鼠体重,腹主动脉取血后处死,收集腹腔内脂肪、子宫、股骨下脂肪以及骨组织并称重。用双能X射线骨密度仪检测离体股骨、胫骨、第5腰椎骨密度和骨矿物含量;用放射免疫方法检测血清FSH、LH、T和E₂水平;用Micro-CT观察L4、股骨远端和胫骨近端微结构变化后用椎体压缩方法检测L4骨生物力学性能指标的变化。实验结果:去卵巢16周后:（1）去卵巢静止组大鼠体重、腹腔内脂肪重量及股骨下脂肪重量显著高于其他两组;子宫重量显著低于假手术组,与去卵巢运动组比较差异无显著性。（2）与去卵巢静止组比较,去卵巢运动组血清E₂水平显著升高,血清T水平显著下降,FSH和LH水平均无统计学差异。（3）去卵巢静止组大鼠L5、股骨远端、胫骨近端、远端BMD及BMC、L4最大载荷、破坏载荷、弹性模量、最大应力、破坏应力、破坏应变均显著低于假手术组;与去卵巢静止组相比,L5、股骨远端、胫骨近端、远端BMD及BMC、最大载荷、破坏载荷、弹性模量、最大应力、破坏应力显著升高。（4）去卵巢静止组大鼠骨小梁排列较其它两组稀疏、骨小梁间隙较大、骨小梁数目较少。去卵巢32周后,与去卵巢静止组相比:（1）去卵巢运动组大鼠体重、腹腔内脂肪重量、股骨下脂肪重量显著增加,骨小梁排列较致密,数目较多;（2）椎骨L4的破坏载荷、弹性模量、破坏应力显著降低,骨小梁间隙较小;（3）其他指标均无显著变化。实验结论:中等强度跑台运动能:（1）抑制去卵巢大鼠腹腔内脂肪和外周脂肪的增加;增加去卵巢大鼠血清E₂水平,降低FSH/LH比值;减缓去卵巢大鼠松质骨骨量的丢失;改善骨组织结构;改善腰椎骨生物力学性能。（2）运动停训16周后,除L5骨密度、弹性模量、破坏应力没有变化以外,运动对其它指标的影响均消失。更多还原

【Abstract】 Objective:Postmenopausal osteoporosis is a commen disease occurred in postmenopausal women. Using ovariectomized-induced osteoporosis model, this paper explored the prevention mechanism of treadmill exercise on the bone loss of ovariectomized rats.Methods:Sixty female Sprague-Dawley rats were randomly divided into following three groups: sham-operation （Sham）, ovariectomized （OVX）, ovariectomized exercised （EX）. After one week of adapatation exercise, the EX rat were regular trained for 45 min at a speed of 18 m.min-1 with 5°slope five times a week. At the end of the exercise training all the three groups were also divided into two subgroups according to the body weight. At week16 or week32, the rats were necrosy by abdimibnal blooding. The abdominal fat, uterus, subcutaneous fat, and bone tissues were isolated and weighted. Then the bone mineral density （BMD） and bone mineral content （BMC） in isolated femur, tibiae, and the fifth lumbar vertebrae were detected by dual-energy X-ray. The serum level of FSH, LH, E2, and T were measured by immuno RIA. After the BMD measurement, the fourth lumbar vertebrae, the distal femur and the proximal tibiae were scanned with Micro-CT. Then the biomechanical properties of femur and lumbar vertebrae were detected by compression tests or three-bending test.Result:After 16 weeks of OVX, （1） the body weight, wet weight of abdominal fat and the wet weight of subcutaneous femur fat in OVX were significantly higher than the other two groups. The uterus wet weight was significantly lower than that of in Sham group while no difference was seen compared with the OVX group. （2） Compared with OVX group, the level of serum E2 in EX group was significantly higher while the serum level of T was significantly lower. No difference was seen in serum level of FSH and LH between EX group and OVX group. （3） The BMD in fifth lumbar vertebrae, the proximal and distal femur, and the proximal tibiae as well as maximum load, failure load, elastic modulus, maximum stress, failure stress, failure strain in the fourth lumbar vertebrae were significantly lower than that of sham group. All these changes could be reversed by EX treatment. （4） Compared with the other two groups, the number of trabecular bone in ovariectomized rats was fewer than the other two groups and the trabecular sparse was great.After 32 weeks of OVX, Compared with OVX group:（1）the body weight ,wet weight of abdominal fat and the wet weight of subcutaneous femur fat in EX group were significantly higher, the number of trabecular bone in EX group rats was more,（2）The failure load, elastic modulus, failure stress in the fourth lumbar vertebrae in EX group were significantly lower than the OVX group,the trabecular sparse was smaller. （3） There were no significant changes in other indicators.Conclusions:（1）Treadmill exercise with moderate intensity could inhibit the increase of body fat, increase serum E₂ levels, improve the bone histology and biomechanical properties of lumbar vertebra in OVX rats.（2） Apart from the effect of exercise training on BMD, elastic modulus, and failure stress, all the effects produced by exercise training in OVX rats had disappeared after detraining.更多还原