MOL BIOMEDICAL CREW MEASUREMENT PROGRAM: HEMATOLOGIC MEASUREMENTS.
Technical rept. Jan-Jun 68,
AEROSPACE MEDICAL LAB (CLINICAL) LACKLAND AFB TEX
Pagination or Media Count:
Space flight is associated with alterations in red cell, white cell and plasma protein composition, but the exact mechanism involved is unknown. Each parameter is exposed to a large variety of stresses, any of which could conceivably act independently, in an additive manner, or even synergistically to produce changes observed thus far. The potential stresses that may influence hematologic homeostasis during manned space flight are weightlessness, atmosphere, transverse acceleration forces, vibration, irradiation and exercise. Complete bed rest is the best available experimental model to test mans potential response to zero gravity. A detailed analysis of the available literature revealed that methodologies differed, but the investigators obtained strikingly consistent results. The red cell mass decreased erythropoiesis. However, data on the Gemini IV, V and VII astronauts suggested need for identifying another mechanism. Use of the diisopropylfluorophosphonate 32 technique to measure survival of erythrocytes is recommended for experiments simulating space flight conditions, because it is more accurate than chromium 51 and other methodologies used. For short-term studies, use of endogenous carbon monoxide production is recommended to approximate more closely the rate of destruction of erythrocytes. Author
- Stress Physiology