跳跃训练对模拟失重大鼠骨密度和骨代谢指标的影响

Effects of jump training on bone mineral density and bone metabolism index of simulated weightlessness rats

目的:通过尾部悬吊模拟后肢失重模型,研究在尾部悬吊期间进行跳跃训练对大鼠骨密度和骨代谢的影响,为宇航员骨质流失的防治提供方法参考。方法:7周龄Wistar雄性大鼠24只,随机分为3组,每组8只,即正常对照组(CON),模拟失重组(SUS)和模拟失重+跳跃训练组(JUM)。通过后肢悬吊的方法制备大鼠后肢模拟失重模型,悬吊和跳跃周期均为3周,3周的干预结束后,测试各组大鼠右侧股骨骨密度和血清骨代谢指标血钙、碱性磷酸酶、骨钙素和抗酒石酸酸性磷酸酶5b。结果:与CON组大鼠相比,SUS组大鼠骨吸收指标血钙(Ca2+)和抗酒石酸酸性磷酸酶5b(TRACP5b)水平均显著增加(P<0.01),骨形成指标血清碱性磷酸酶(ALP)和骨钙素(BGP)水平显著降低(P<0.05),骨密度显著下降(P<0.01);与SUS组大鼠相比,JUM组大鼠骨吸收指标血钙(Ca2+)和抗酒石酸酸性磷酸酶5b(TRACP5b)水平显著降低,骨形成指标血清碱性磷酸酶(ALP)和骨钙素(BGP)水平显著增加,骨密度显著升高(P<0.01)。结论:尾部悬吊模拟后肢失重可导致大鼠骨吸收作用增强,骨形成作用降低,骨密度下降。而在模拟失重期间进行跳跃训练可有效抑制大鼠骨吸收和增强其骨形成,从而有效抑制尾部悬吊大鼠骨密度的下降。

Objective： Preparing of simulated hindlimb weightlessness model by tail suspension, we study the effects of jump training during simulated weightlessness on bone mineral density and bone metabolism of the rats, to provide reference for the prevention of astronaut bone loss. Methods：24 7-week-old male Wistar rats were randomly divided into 3 groups, 8 rats in each group, they are normal control group （CON）, simulated weightlessness group （SUS） and simulated weightlessness ＋ jump training group （JUM）. We prepare rat hindlimb weightlessness simulation model by the methods of hindlimb suspension. Suspension and jump training time is 3 weeks. After 3 weeks of the intervention, testing femur bone density and bone metabolism of serum calcium, alkaline phospha-tase, osteocalcin and tartrate-resistant acid phosphatase 5b of each rat. Results：compared with the rats in CON group, SUS group rats bone absorption index （Ca^2＋ ） and serum tartrate-resistant acid phosphatase 5b （TRACP5b） levels were significantly increased （P 〈 0.01 ）, bone foruaation markers of serum alkaline phosphatase （ALP） and Osteocalcin （BGP） levels were significantly reduced （P 〈 0.05）, bone density decreased significantly （P 〈 0.01 ） ; Compared with the rats of SUS group, the rats of JUM group bone absorption index （ Ca^2 ＋ ） and serum tartrate -resistant acid phosphatase 5b （TRACP5b） level were significantly decreased, bone formation markers of serum alkaline phos- phatase （ALP） and Osteoealcin （BGP） levels were significantly increased, bone density increased significantly （P 〈 0.01 ）. Conclusion： Simulated hindlimb weightloss by tail suspension can lead to enhanced bone resorption, decreased bone formation and decreased hone density of the rats. Jump training during the simulated weightlessness can effectively inhibit bone resorption and increased bone formation of the rat, thereby effectively inhibit the decrease of bone density of the tail - suspen-ded rats.