EXPERIMENT INFORMATION
Biological Rhythm and Temperature Regulation: II. Metabolism (COS 2044-24)
Species Studied
Scientific Name: Macaca mulatta Species: Monkey Strain: Rhesus
Objectives:In this experiment, energy expenditure was measured in Rhesus monkeys using the doubly labeled water (2H218O) method. Determinations were made during space flight and during postflight ground control. The doubly labeled water method is the only method available for continuously measuring energy expenditure during space flight considering the severely restricted conditions of spacecraft. Therefore, this study focused on the development and use of this procedure on nonhuman primates during space flight.
++ -- View more
Approach:
When doubly labeled water is given orally, it mixes with body water in about three hours. The two isotopes then leave the body at different rates; 2H leaves as water, mainly in urine, whereas 18O leaves both as water and exhaled CO2. Thus the turnover rate of isotopic hydrogen and oxygen labeled differ, the difference proportional to the rate of CO2 production. Monkeys were dosed (3-5 ml) three days preflight. Urine samples (3 ml) were collected following the dose to determine body water pool size, as well as pre- and postflight. Animals were redosed with 18O postflight to determine any changes in body protein and fat content.
Results:
The data from this study demonstrate the viability of this technique as an inflight measure of metabolism, although accuracy could be enhanced by collecting more urine samples. The total body water (TBW) in the flight study of 2.986 corresponds to 77.76% of the animal's body weight, suggesting that the animal was in a dehydrated state when the measurements were made. The flight energy expenditure value of 266 kcal/monkey/day or 69.3 kcal/kg/day appears physiological. Due to a problematic sample, the postflight TBW could not be determined.
Fuller, C.A. et al.: Circadian Rhythms and Temperature Regulation During Spaceflight: II. Metabolism. Final Reports of the U.S. Experiments Flown on the Soviet Biosatellite Cosmos 2044. Vol. 2. J.P. Connolly, R.E. Grindeland, and R.W. Ballard, eds., NASA TM-108802, 1994, pp. 361-383.
Basal metabolism
Body temperature regulation
Body water
Deuterium
Energy metabolism
++ -- View more
Heart rate
Oxygen isotopes
Skin temperature
Data Availability
Archive is complete. No data sets are available for this experiment. Please
Contact LSDA if you know of available data for this investigation.
Activity, Carbon dioxide production, primate, Doubly labeled water (2H218O) method
Activity, Protein synthesis, whole body, primate, Doubly labeled water (2H218O) method
Consumption, Diet, rat, primate, Measured water
Content, Doubly labeled water (DLW), urine, primate, Isotopic quantities
Respiration, Respiratory exchange quotient, Primate, Radioisotopic tracers (2 H, 18 O)
++ -- View more
Volume, Total body, primate, Isotopic, calculation
Volume, Urine, primate, Measurement (cc)
Mission/Study Information
Mission
|
Launch/Start Date
|
Landing/End Date
|
Duration
|
Cosmos 2044
|
09/15/1989
|
09/29/1989
|
14 days
|
Managing NASA Center
Ames Research Center (ARC)
Responsible NASA Representative
Ames Research Center LSDA Level 3
Project Manager: Martha Del Alto
Institutional Support
National Aeronautics and Space Administration (NASA)
Alternate Experiment Name
Similar Experiments or Analyses