title: [Serum enzyme activity of healthy subjects during modeling of the effects of weightlessness].
abstract: The enzymic activity of blood of healthy male volunteers was examined during 8-day bed rest in the horizontal and head-down (-6 degrees) position, water immersion up to the neck and 6-hour head-down tilt (-15 degrees). Alkaline phosphatase, cholinesterase (CE), leucine arylamidase (LA), glutamate dehydrogenase (GDH) and gamma-glutamyl transpeptidase (GGTP) were measured. During horizontal bed rest the activities of all the enzymes, except for GDH, decreased in a moderate degree which was very distinct at an early stage of exposure. The activity of GDH and CE decreased significantly after the exposure. The enzymic activity tended to decline during head-down tilt at -6 degrees. The LA and GGTP activity decreased to a greater extent, being statistically significant during head-down tilt at -6 degrees and in the recovery period. The enzymic activity insignificantly increased during water immersion and 6-hour head-down tilt at -15 degrees, remaining in some cases elevated during 5 days after exposure. The lower activity of enzymes (which was significant for some of them) during horizontal and antiorthostatic bed rest was primarily associated with diminished motor activity, whereas increased enzymic activity was related to the gravity-induced blood shift to the intrathoracic area.
authors.forename: I A
authors.initials: IA
authors.lastname: Popova
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D001510:Bed Rest; D002802:Cholinesterases / Q000097:blood; D004798:Enzymes / Q000097:blood*; D005969:Glutamate Dehydrogenase / Q000097:blood; D006801:Humans; D007101:Immersion / Q000503:physiopathology; D007931:Leucyl Aminopeptidase / Q000097:blood; D008297:Male; D008954:Models, Biological; D011187:Posture; D014893:Weightlessness; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D004798:Enzymes; D005969:Glutamate Dehydrogenase; D005723:gamma-Glutamyltransferase; D002802:Cholinesterases; D000469:Alkaline Phosphatase; D007931:Leucyl Aminopeptidase
vernacular_title: Aktivnost' fermentov syvorotki krovi zdorovogo cheloveka pri modelirovanii éffektov nevesomosti.