Convertino V, Hoffler G W
Biomedical Operation and Research Office, Kennedy Space Center.
J Fla Med Assoc. 1992 Aug;79(8):517-24.
Experiments during spaceflight and its groundbase analog, bedrest, provide consistent data which demonstrate that numerous changes in cardiovascular function occur as part of the physiological adaptation process to the microgravity environment. These include elevated heart rate and venous compliance, lowered blood volume, central venous pressure and stroke volume, and attenuated autonomic reflex functions. Although most of these adaptations are not functionally apparent during microgravity exposure, they manifest themselves during the return to the gravitational challenge of earth's terrestrial environment as orthostatic hypotension and instability, a condition which could compromise safety, health and productivity. Development and application of effective and efficient countermeasures such as saline "loading," intermittent venous pooling, pharmacological treatments, and exercise have become primary emphases of the space life sciences research effort with only limited success. Successful development of countermeasures will require knowledge of the physiological mechanisms underlying cardiovascular adaptation to microgravity which can be obtained only through controlled, parallel groundbased research to complement carefully designed flight experiments. Continued research will provide benefits for both space and clinical applications as well as enhance the basic understanding of cardiovascular homeostasis in humans.
太空飞行及其地面模拟实验——卧床休息，提供了一致的数据，表明心血管功能发生了许多变化，这是对微重力环境生理适应过程的一部分。这些变化包括心率加快和静脉顺应性增加、血容量降低、中心静脉压和心输出量降低，以及自主反射功能减弱。虽然这些适应在微重力暴露期间大多没有明显的功能表现，但在返回地球重力环境时，它们会表现为体位性低血压和不稳定，这种情况可能会危及安全、健康和工作效率。开发和应用有效的对抗措施，如盐水“负荷”、间歇性静脉充血、药物治疗和运动，已成为太空生命科学研究工作的主要重点，但取得的成功有限。对抗措施的成功开发需要了解心血管适应微重力的生理机制，而这只能通过可控的、平行的地面研究来获得，以补充精心设计的飞行实验。持续的研究将为太空和临床应用带来益处，并增进对人类心血管稳态的基本理解。
