Zhang L F, Yu Z B, Ma J, Mao Q W
Department of Aerospace Physiology, The Fourth Military Medical University, Xi'an, PR China.
Aviat Space Environ Med. 2001 Jun;72(6):567-75.
Studies on the mechanisms of cardiovascular dysfunction after space-flight are important to illustrate the cardiovascular effect of microgravity and develop appropriate multi-system countermeasures for future long-duration spaceflights. Over the past 10 yr, we have systematically studied the adaptational changes in structure and function of both the heart and vessels, using the tail-suspension rat model to simulate microgravity effects. Our results indicate that simulated microgravity induced atrophic changes and reduced contractility of the heart muscle, and upward- and downward-regulation in structure, function, and innervation state of vessels in the brain and hind body of the rat. In addition, more recent advances in relevant ground-based and space-flight studies from different laboratories have also been reviewed. Based on these studies, it has been speculated that, in addition to hypovolemia, the microgravity-induced adaptational changes in the structure and function of the two main effectors of the cardiovascular system, i.e., the arterial smooth muscle and the cardiac muscle, might be among the most important mechanisms responsible for postflight cardiovascular dysfunction and orthostatic intolerance. In this paper we will review the available evidence with comments.
研究太空飞行后心血管功能障碍的机制，对于阐明微重力对心血管系统的影响以及为未来长期太空飞行制定合适的多系统应对措施具有重要意义。在过去10年中，我们利用尾悬吊大鼠模型模拟微重力效应，系统地研究了心脏和血管结构与功能的适应性变化。我们的研究结果表明，模拟微重力会导致心肌萎缩和收缩力下降，以及大鼠脑部和后躯血管在结构、功能和神经支配状态上的上调和下调。此外，还综述了来自不同实验室的相关地面研究和太空飞行研究的最新进展。基于这些研究，据推测，除血容量减少外，心血管系统的两个主要效应器即动脉平滑肌和心肌在结构和功能上的微重力诱导适应性变化，可能是飞行后心血管功能障碍和体位性不耐受的最重要机制之一。在本文中，我们将对现有证据进行综述并加以评论。
