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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Effect of bed rest on blood volume, urinary volume, and urinary electrolyte excretion
Bed rest effect on plasma levels and urinary excretion of hydroxycorticosteroids
Mood, motility, and 17-hydroxycorticoid excretion in cyclic manic-depressive patient
Comparative morphology and physiology of excretion
Excretion of catecholamines and metabolites in project mercury pilots during training and space flight
Urinary excretion of 3-methoxy-4-hydroxymandelic acid during dreaming sleep in man
Physiologic and metabolic changes in monkeys on various diets during couch restraint and nonrestraint determined by body weight, food consumption and urinary excretion data
Physiologic and metabolic changes in monkeys on various space diets during couch restraint and nonrestraint, emphasizing urinary and fecal Ca and P excretion data relationship
Liver xanthine dehydrogenase change relation to uric acid excretion during adaptation period in chicks fed 25-75 percent isolated soybean protein
Electron computer analyses of circadian acrophases of 17-hydroxycorticosteroid excretion with midsleep as phase reference in humans from various cultures
Renal effects of moderate hypoxia exposure in mice as reflected in urine volume and electrolyte excretion patterns during four days at simulated altitude
Intrarenal capillary hydrostatic pressure effect on hemodynamically induced changes in sodium excretion
Seventeen KGS (17-Ketogenic steroids) and Na/K were determined in 19 urine specimens collected by each of 4 crewmen during the 90-day test. The specimens represented 10% aliquots of 24-hour collections stored frozen onboard the simulator until passthrough. Electrolytes were analyzed immediately after sample passthrough while the steroids were determined post-test on aliquots of the original sample held at 203 K. Steroid data was corrected for body weight and also for analytical variation in the laboratory urine pool control. Long-term nonspecific responses to low-level stress appear to be reflected by the individual and group mean 17-KGS excretion patterns. The first 39 and the last 20 days of the test were significantly different--and presumably more stressful to the crew--than the period from days 39 to 67. Reduction of adrenocortical function during the mid-test phase is attributed to either an adaptation to chronic or intermittent stress or was the result of an actual reduction in the operational demands of the test during this time. Most remarkable of the metabolic findings is the prevalance of high Na/K ratios and an abrupt peak on day 74 for all 4 crewmen.
A study was conducted to determine the baseline 24-hr urinary excretion values in the young, unrestrained chimpanzee, and also changes in urinary values, if any, induced by the two-day food deprivation stress. Urine was analyzed for volume, osmolarity, creatinine, creatine, urea nitrogen, 17-hydroxycorticosteroids (17-OHCS), 3-methoxy-4-hydroxymandelic acid (VMA), calcium, and inorganic phosphorus. Significant increases due to food deprivation stress were observed for volume, creatine, urea nitrogen, 17-OHCS, VMA, and phosphorus values, with significant decreases in osmolarity and calcium. All values approached normal levels by the second poststress day. No significant changes were observed in creatinine. A comparison is drawn between human and chimpanzee adaptation to stress.
Effect of actinomycin D on aldosterone-mediated changes in electrolyte excretion.
Bone resorption was measured directly in flight and synchronous control rats during COSMOS 1129. Continuous tracer administration techniques were used, with replacement of dietary calcium with isotopically enriched Ca-40 and measurement by neutron activation analysis of the Ca-48 released by the skeleton. There is no large change in bone resorption in rats at the end of 20 days of spaceflight as has been found for bone formation. Based on the time course of changes, the measured 20-25 percent decrease in resorption is probably secondary to a decrease in total body calcium turnover. The excretion of sodium, potassium, and zinc all increase during flight, sodium and potassium to a level four to five times control values.
Real and simulated microgravity impairs T secretion both in animals and in the human. To verify whether hypergravity might enhance T secretion as a consequence of an opposite mechanical effect, 6 male monkeys were centrifuged at 2 G for 3 weeks after a 1 G stabilization period lasting 3 weeks and then taken back to 1 G for 1 week and urine were collected daily for T excretion measurement. Significantly higher level were observed during the initial 2 G phase as compared to pre- and post centrifugation periods and the trend was the same during the remaining 2 G period. This may reflect changes in testicular perfusion rather than endocrine adaptation per se.