摘要
目的研究抗阻力锻炼对8周模拟失重大鼠骨丢失的防护效果。方法 40只Wister大鼠随机分为对照组(Con)、尾吊组(HU)、尾吊+站立组(HU+ST)、尾吊+站立抗阻力锻炼组(HU+RE)。尾吊时间8周,尾吊期间锻炼组大鼠每周以65%～75%1RM进行抗阻力锻炼5 d,每天4组×12次。尾吊后分别用MicroCT和三点弯曲实验测量骨密度和骨生物力学参数。结果与对照组相比,8周尾部悬吊大鼠松质骨骨密度、骨体积分数和骨小梁厚度明显降低,骨小梁分离度增大,股骨最大载荷和刚性系数也显著降低。悬吊组和站立组大鼠股骨各测量参数之间没有显著区别。抗阻力锻炼明显提高了松质骨骨密度、骨体积分数和骨小梁厚度,降低了骨小梁分离度。锻炼组大鼠股骨最大载荷和刚性系数明显高于悬吊组和站立组;刚性系数高于悬吊组,与站立组没有明显差别。结论抗阻力锻炼能够有效对抗尾吊大鼠骨密度的降低,减缓了骨强度的下降。
Objective To determine the effectiveness of resistance exercise on attenuating bone loss in 8-week hindlimb unloaded rats.Methods Forty male Wistar rats were divided randomly into 4 groups： control group（Con）,hindlimb unloading group（HU）,hindlimb unloading ＋ stand group（HU＋ST）,and hindlimb unloading ＋ resistance exercise group（HU＋RE）.In HU＋RE,10 rats were performed resistance exercise during 8 weeks.Resistance exercise was performed with 4 sets of 12 repetitions 5 days/week using 65% to 75% of one repetition maximum（1RM）.At the end of 8 weeks resistance exercise,bone mineral density（BMD） and biomechanical properties of the femur were measured with MicroCT and three points bending test respectively.Results Compared with Con,8 weeks hindlimb unloading induced a decrease of bone mineral density（BMD）,bone volume fraction（BV/TV）,trabecular thickness（Tb.Th） and an increase of trabecular separation（Tb.Sp） in femoral cancellous bone.Maximum load and stiffness of femoral midshaft decreased significantly after 8 weeks hindlimb unloading.No significant differences were observed for all bone parameters when comparing HU and HU＋ST rats.Compared with HU and HU＋ST,resistance exercise improved BMD,BV/TV,Tb.Th,and reduced Tb.Sp in femoral cancellous bone.In HU＋RE,Maximum load of femoral midshaft was significantly higher than that in HU and HU＋ST,while lower than that in C.Stiffness of femoral midshaft in HU＋RE was significantly higher than that in HU but no significant difference than HU＋ST. Conclusion Resistance exercise can counter bone loss effectively and mitigate the bone strength reduction induced by simulated weightlessness.
出处
《航天医学与医学工程》
CAS
CSCD
北大核心
2011年第1期5-8,共4页
Space Medicine & Medical Engineering
基金
中国航天医学工程预先研究项目(SJ200802)
关键词
失重模拟
尾吊
抗阻力锻炼
骨丢失
weightlessness simulation
tail-suspension
resistance exercise
bone loss
