失重骨丢失与防治措施研究进展  

Research development of effect of weightlessness on bone loss and countermeasure

作　　者：张红[1] 刘成林[1] 白树民[1] 

机构地区：[1]航天医学工程研究所,北京100094

出　　处：《中国骨质疏松杂志》2008年第10期754-758,共5页Chinese Journal of Osteoporosis

摘　　要：笔者综述了部分干预措施在稳定钙平衡和骨代谢以及防治骨量丢失方面的作用。空间飞行中提高钙的摄入量和补充维生素D,通过增加骨化三醇水平,能防止血清钙水平升高,维生素K能抵抗骨形成的减少。然而,目前还没有防止空间飞行航天员发生骨质疏松的有效药剂。在尾吊成年大鼠模拟失重动物模型中,应用双膦酸盐能够防护胫骨的松质骨量丢失,睾酮和维生素K2通过防止骨吸收增加和骨形成减少,能够对抗后肢的BMD下降。然而,这些药剂是否能够防止尾吊模拟失重大鼠引起的皮质骨骨量丢失尚不清楚。因此,除了补充钙、维生素D、维生素K,有待寻找有效的兼具抑制吸收和促合成代谢的药物来维持空间飞行中航天员的钙平衡和骨代谢,从而防护骨量丢失。This paper reviews the interventions to stabilize calcium balance and bone metabolism and prevent bone loss in astronauts during weightlessness and simulated weightlessness. Weightlessness during spaceflight results in calcium, vitamin D, and vitamin K deficiency, increases urinary calcium excretion, decreases intestinal calcium absorption, and increases serum calcium level, with decreased levels of serum parathyroid hormone and ealeitriol. Bone resorption is increased, whereas bone formation is decreased. High calcium intake and vitamin D supplementation during spaceflight does not affect bone metabolism, but prevents an elevation of serum calcium level through increased calcitriol level, while vitamin K counteracts the reduction in bone formation. However, there are no data to show the efficacy of pharmaceutical agents for prevention of development of osteoporesis in astronauts during flight, although the preventative effect of bisphosphonates, testosterone, and vitamin K2 on cancellous bone loss in the tibia or BMD loss in the hindlimb was reported in tail-suspended mature rats. It still remains uncertain whether these agents can prevent cortical bone loss caused by weightlessness in tailsuspended rats. Therefore, in addition to calcium, vitamin D, and vitamin K supplementation, agents that have both potent anti-resorptive and anabolic effects on cancellous and cortical hone may be needed to stabilize calcium balance and bone metabolism and prevent bone loss in astronauts during spaceflight.

关 键 词：骨形成 骨吸收 钙 失重 模拟失重 骨质疏松 

分 类 号：R857[医药卫生—航空、航天与航海医学]