title: Short-term space flight on nitrogenous compounds, lipoproteins, and serum proteins.
abstract: Biochemical variables in blood were measured in venous blood samples from 38 to 72 Space Shuttle astronauts before and immediately after flights of 2 to 11 days. Mean pre- and postflight values were compared using the paired t-test or the Wilcoxon signed-rank test. The largest change in serum enzymes was a 21% increase (P = .0014) in gamma-glutamyl-transpeptidase, which may have been related to stress. The median value of apolipoprotein (apo) A-I decreased from 152 to 127 mg/dL (P < .0001), but the change in apo B (77 to 73 mg/dL) was not statistically significant, and the mean apo A-I/apo B ratio remained well above 1.5. A decrease in dietary fat and cholesterol intake during shuttle missions may have been a cause of the change in apo A-I. Twelve of the 16 nonenzyme serum proteins measured were significantly elevated (P < .05), possibly because of hemoconcentration and increased protein catabolism. The 56% increase in haptoglobin may be related to release of suppressed erythropoiesis at landing.
authors.affiliation: Biomedical Operations and Research Branch, National Aeronautics and Space Administration, Johnson Space Center, Houston, Texas.
authors.forename: C S
authors.initials: CS
authors.lastname: Leach
authors.forename: H W
authors.initials: HW
authors.lastname: Lane
authors.forename: J M
authors.initials: JM
authors.lastname: Krauhs
mesh_terms: D000328:Adult; D001054:Apolipoproteins A / Q000032:analysis; D001055:Apolipoproteins B / Q000032:analysis; D001798:Blood Proteins / Q000032:analysis* / Q000378:metabolism; D004032:Diet; D005260:Female; D006801:Humans; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D017672:Nitrogen Compounds / Q000097:blood*; D013026:Space Flight; D013997:Time Factors; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D001054:Apolipoproteins A; D001055:Apolipoproteins B; D001798:Blood Proteins; D008074:Lipoproteins; D017672:Nitrogen Compounds; D005723:gamma-Glutamyltransferase