RESULTS
The last group of subjects for this experiment returned after Expedition 5. Data from all
subjects were collected successfully. Findings show venous-arteriolar reflex reduced
subcutaneous blood flow by 37 +/- 9% before flight and by 64 +/- 8% following landing, with no
statistical difference between the 2 responses. The mean arterial pressures and heart rates in
supine astronauts were very similar before and after flight. These data indicate that this reflex
is not attenuated by weightlessness and suggests that the venous-arteriolar reflex is not a
contributor to postflight orthostatic intolerance (Gabrielsen 2006).
PUBLICATION(S)
Gabrielsen A, Norsk P. Effect of spaceflight on the subcutaneous veno-arteriolar reflex in the
human lower leg. Journal of Applied Physiology. 2007;103(3):959-962. doi: 10.?1152/00899.
2006.
This investigation is complete and all results are published.