Role of muscle spindle in weightlessness-induced amyotrophia and muscle pain

Abstract

To date, the medium and long-term space flight is urgent in need and has become a major task of our manned space flight program. There is no doubt that medium and long-term space flight has serious damaging impact upon human physiological systems. For instance, atrophy of the lower limb anti-gravity muscle can be induced during the space flight. Muscle atrophy significantly affects the flight of astronauts in space. Most importantly, it influences the precise manipulation of the astronauts and their response capacity to emergencies on returning to the atmosphere from space. Muscle atrophy caused by weightlessness may also seriously disrupt the normal life and work of the astronauts during the re-adaptation period. Here we summarize the corresponding research concentrating on weightlessness-induced changes of muscular structure and function. By combining research on muscle pain, which is a common clinical pain disease, we further provide a hypothesis concerning a dynamic feedback model of “weightlessness condition ⇒ muscular atrophy ⇔ muscle pain”. This may be useful to explore the neural mechanisms underlying the occurrence and development of muscular atrophy and muscle pain, through the key study of muscle spindle, and furthermore provide more effective therapy for clinical treatment.

摘要

目前, 中、 长期航天飞行会对航天员的器官系统造成损害, 如离心性下肢抗重力肌发生明显萎缩, 直接影响宇航员的太空飞行及返回大气层着陆时的准确操纵与应急离舱能力。 肌肉萎缩还会严重影响宇航员返回地面后的正常工作和生活。 本文将对失重或模拟失重环境下的肌肉结构及功能变化的相关研究给予一定的文献回顾。 结合相关肌肉痛研究, 我们提出“肌萎缩(肌梭变化为核心)-肌肉痛”这一动态双向可塑反应模式假设。 通过以肌梭为研究核心的肌萎缩/肌肉痛研究, 可能会更好地阐明肌肉萎缩及肌肉痛发生过程中的神经机理, 并为临床提供更好的治疗方案。