title: Regulation and distribution of body fluid during a 6-day head-down tilt study in a randomized cross-over design.
abstract: Head down tilt (-6 degrees HDT) examinations are commonly used simulation models for various microgravity induced changes in body functions. Body fluid distribution (by means of dye dilution and two independent multifrequency impedance techniques), water- and sodium-handling, and the plasma/serum concentrations of fluid balance related hormones have been determined in a randomized, controlled, cross-over study in 8 healthy test subjects. The comparison of responses to HDT and an upright control position with respective experiences from space shows some similarities but also various discrepancies between the terrestrial simulation and real microgravity.
authors.affiliation: Institute of Aerospace Medicine, German Aerospace Center DLR, Cologne, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Drummer
authors.forename: M
authors.initials: M
authors.lastname: Heer
authors.forename: M
authors.initials: M
authors.lastname: Joosten
authors.forename: I
authors.initials: I
authors.lastname: Störmer
authors.forename: C
authors.initials: C
authors.lastname: Hesse
authors.forename: L
authors.initials: L
authors.lastname: Beck
authors.forename: G
authors.initials: G
authors.lastname: Wolfram
authors.forename: F
authors.initials: F
authors.lastname: Baisch
mesh_terms: D001510:Bed Rest; D001835:Body Weight; D004231:Diuresis; D017097:Electric Impedance; D005110:Extracellular Space / Q000502:physiology*; D018495:Fluid Shifts / Q000502:physiology*; D018475:Head-Down Tilt; D006801:Humans; D010953:Plasma Volume / Q000502:physiology*; D012964:Sodium / Q000378:metabolism; D013997:Time Factors; D018474:Weightlessness Simulation
chemical_list: D012964:Sodium