The regulation of fluid and electrolyte metabolism in weightlessnessEndocrine and biochemical changes in astronauts caused by weightlessness are discussed. Translocation of fluid from the extremities to the head and chest at the onset of weightlessness is thought to lead to the establishment of a lower blood volume as an adaptation to microgravity. Results of Skylab experiments indicate that several other regulatory systems have lower homeostatic set points during space flight. Inflight blood samples from three Spacelab flights show increased antidiuretic hormone throughout these short flights and decreased aldosterone and cortisol after 3 days. Results help to explain blood hypoosmolality and hyponatremia but do not explain what happens between the onset of weightlessness and hormone changes. Other factors such as natriuretic peptides and changes in renal function are being studied to elucidate the physiologic adaptation mechanisms.
Document ID
19870001246
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Leach, C. S. (NASA Lyndon B. Johnson Space Center Houston, TX, United States)
Johnson, P. C. (NASA Lyndon B. Johnson Space Center Houston, TX, United States)
Cintron, N. M. (NASA Lyndon B. Johnson Space Center Houston, TX, United States)
Date Acquired
August 13, 2013
Publication Date
February 1, 1986
Publication Information
Publication: ESA Proceedings of 2nd International Conference on Space Physiology