4 Laboratory (Flight Backup Subjects)
Key Flight Hardware
Primate Life Support System; Urine Analyzer
Objectives/Hypothesis
Among other Biosatellite III objectives, the urine analyses, together with appro-
priate analysis of feces and a knowledge of quantity and composition of food,
were to permit computation of the calcium balance of the animal in weightless-
ness, thereby allowing assessment of the degree of possible skeletal demineral-
ization. Also, measurement of the excretion rate of creatinine and creatine
was expected to shed some light on the question of whether or not significant
disuse atrophy of the musculature occurs as a consequence of space flight.
Approach or Method
The flight Urine Analyzer included a case which contained a urine sample
accumulator, a calcium analyzer, a creatinine-creatine analyzer, reagent storage
bags, logic sequencers, a data handling system and a power converter. Once every
six hours during flight urine sample aliquots were analyzed and telemetered
to the ground and correlated with laboratory animals. Collections for flight
and control animals began seventeen days preflight, and continued through flight
termination. Bladder and vascular catheters were surgically implanted thirteen,
twelve, and eight days preflight.
Results
Three of the flight candidate animals, including the flight animal, experienced
a profound hypocalciuria in association with the preflight surgery, which was
tran- siently reversed but then recurred ten to fourteen days after initial
occurrence. This obscured any possible effects of weightlessness on urine calcium
excretion rate in the flight animal. On a more positive side, the development
of a fully automated urine analyzer which permitted continuous measurement of
these three substrates (calcium, creatinine, and creatine) during the flight
ranks as an out- standing accomplishment. Other results suggest that while anorexia
occurred in the flight monkey, there was no evidence of diuresis, and that the
urine excretion rate of creatinine is depressed in monkey and man, in the weightless
state.
Publications
Experiment Reference Number: BIO3-4
Pace, N. et al.: Urine Excretion Rates of Calcium, Creatine, and Creatinine
in Test Monkeys and Flight Monkey Used for NASA Biosatellite III. NASA CR-114425,
1971.
¥ = publication of related ground-based study