前庭系统适应性变化对心血管调节和立位耐力的影响

空间飞行初期人体感受到的空间适应综合征，主要由前庭传入的改变和体液头向分布引起，这种适应性的逆向变化同样发生在人体由微重力返回正常1G重力时，造成航天员返回后出现步态不稳及立位耐力下降。动物模型的证据和人体实验的部分数据表明，前庭系统通过自主神经系统影响心血管调节，其中耳石感受器的传入起着重要作用。由于心血管调节异常引起的立位耐力下降是载人航天的重要医学问题。在心血管功能和立位耐力下降过程中前庭系统功能变化有重要影响。

Effects of Adaptive Changes of Vestibular System on Cardiovascular Regulation and Orthostatic Tolerance

Astronauts may experience Space Adaptation Syndrome at the primary period in spaceflight. It is widely accepted that it is mainly caused by vestibular adaptive changes. The reverse changes of adaptation present after the return from weightlessness to normal 1 G. It may cause astronauts' postural instability and orthostatic intolerance. Evidences from animal model and some data from humans suggest that the vestibular system have influences on the sympathetic nervous system and cardiovascular control. The inputs that appear to be critical in producing these responses come from otolith receptors. The important medical problem--orthostatic intolerance in space medicine is mainly caused by cardiovascular abnormal control. It is possible that vestibular adaptive changes under microgravity may have its influence on the cardiovascular function and orthostatic intolerance.