title: Studies of the protein and the energy metabolism in man during a wintering in Antarctica.
abstract: During the 29th Soviet Antarctic Expedition in Novolazarevskaya from March 1984 to March 1985, the protein and energy metabolisms were studied in six expeditioners from the German Democratic Republic. The investigations were carried out at the beginning of the expedition (May), during the polar night (July) and during the polar day (December). The effect of a special stress situation (sledge trek in April 1984) was investigated in one subject. The stable nitrogen isotope (15)N was used to study the protein metabolism. The assessment of the energy metabolism was based on the oxygen consumption, which was determined by means of a spirograph. In addition, the vital capacity, the breath minute volume, the blood pressure, etc. were measured. The following results were obtained: During the polar night, the utilisation of the dietary proteins and the whole body protein synthesis calculated by means of the (15)N excretion of the total nitrogen in urine were greater (73.6±0.9 % and 3.48±0.17 g protein d(-1) kg(-1), n=3) than the respective values during the polar day (69.7±1.2, p<0.05, n=3 and 3.05±0.07, p<0.05, n=3) and at the beginning of the expedition (69.6±1.4, p<0.02, n=5 and 2.81±0.09, p<0.01, n=5). The lowest values (58.0 % and 2.43 g protein d(-1) kg(-1)) were obtained in the subject after the trek. The resting metabolic rate (in kJ d(-1) m(-2)) was decreased during the polar night (45.6±5.0, n=4) in comparison with the polar day (61.5±11.3, n=3) and the beginning of the expedition (52.3±9.6, n=4) with p<0.01 in both cases.
authors.affiliation: Central Institute for Isotope and Radiation Research, Academy of Sciences of the GDR, Leipzig, Germany. junghans@fbn-dummerstorf.de
authors.forename: Peter
authors.initials: P
authors.lastname: Junghans
authors.forename: Georg
authors.initials: G
authors.lastname: Schrader
authors.forename: Hans
authors.initials: H
authors.lastname: Faust
authors.forename: Barbara
authors.initials: B
authors.lastname: Wagner
authors.forename: Klaus
authors.initials: K
authors.lastname: Hirschberg
authors.forename: Rolf
authors.initials: R
authors.lastname: Reinhardt
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000328:Adult; D000864:Antarctic Regions; D003080:Cold Temperature; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000097:blood / Q000652:urine; D009587:Nitrogen Isotopes / Q000097:blood / Q000652:urine; D010101:Oxygen Consumption / Q000502:physiology; D014176:Protein Biosynthesis / Q000502:physiology; D011506:Proteins / Q000378:metabolism*; D012621:Seasons; D013147:Spirometry; D013315:Stress, Psychological / Q000097:blood / Q000378:metabolism / Q000652:urine
chemical_list: D009587:Nitrogen Isotopes; D011506:Proteins; D009584:Nitrogen