title: Cholesterol in serum lipoprotein fractions after spaceflight.
abstract: Cholesterol, triglycerides, very low density lipoprotein cholesterol (VLDL-C), low density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C) were measured in blood samples from 125 crewmembers on the first 24 space shuttle flights. Samples were obtained before, immediately after, and 3-23 days after spaceflight. On landing day, only HDL-C was significantly changed from its preflight level; it had decreased 12.8%. Later in the postflight period, total cholesterol and LDL-C as well as HDL-C decreased significantly. Possible causes of these decreases in estimated cholesterol content of lipoprotein fractions include increased levels of thyroxine during flight and reduced physical activity. The postflight decrease in HDL-C is not considered to have clinical significance for shuttle astronauts, but lipoproteins and apolipoproteins should be measured in blood drawn during longer missions.
authors.affiliation: Biomedical Laboratories Branch, Johnson Space Center, Houston, Texas 77058.
authors.forename: C S
authors.initials: CS
authors.lastname: Leach
authors.forename: P C
authors.initials: PC
authors.lastname: Johnson
authors.forename: J M
authors.initials: JM
authors.lastname: Krauhs
authors.forename: N M
authors.initials: NM
authors.lastname: Cintrón
mesh_terms: D000328:Adult; D002784:Cholesterol / Q000097:blood*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000652:urine; D013026:Space Flight; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014280:Triglycerides / Q000097:blood
chemical_list: D007328:Insulin; D008074:Lipoproteins; D014280:Triglycerides; D013972:Thyrotropin; D002784:Cholesterol; D013974:Thyroxine; D009638:Norepinephrine