title: Intermittent hypobaric hypoxia increases the ability of neutrophils to generate superoxide anion in humans.
abstract: 1. We investigated the effect of intermittent exposure to hypobaric hypoxia on the ability of neutrophils to generate.O2-. 2. Seven male volunteers were exposed intermittently to hypobaric hypoxia, equivalent to an altitude of 4500 m, for 7 successive days. Peripheral blood samples were collected before and after the 2 h course of hypobaric hypoxia on days 1 and 7 and neutrophils were subjected to a chemiluminescence assay for.O2- production. 3. On day 1, 2 h exposure to hypobaric hypoxia induced granulocytosis (P < 0.01), but the ability of neutrophils to generate.O2- was unchanged. 4. On day 7, such granulocytosis was not observed, suggesting acclimatization to hypobaric hypoxia. 5. The ability of neutrophils to generate.O2- was significantly increased on day 7 (P < 0.01), although there was no definite change in the mRNA expression of NADPH oxidase subunits in the cells. 6. The results suggest that the ability of neutrophils to generate.O2- may be gradually potentiated by intermittent exposure to hypobaric hypoxia, even after the number of neutrophils in peripheral blood stabilizes.
authors.affiliation: Department of Molecular Predictive Medicine and Sport Science, Kyorin University, School of Medicine, 6-20-2 Shunkawa, Mitaka, Tokyo 181-8611, Japan. yhitomi@kyorin-u.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Hitomi
authors.forename: M
authors.initials: M
authors.lastname: Miyamura
authors.forename: S
authors.initials: S
authors.lastname: Mori
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Kizaki
authors.forename: C
authors.initials: C
authors.lastname: Itoh
authors.forename: K
authors.initials: K
authors.lastname: Murakami
authors.forename: S
authors.initials: S
authors.lastname: Haga
authors.forename: H
authors.initials: H
authors.lastname: Ohno
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002452:Cell Count / Q000379:methods; D006801:Humans; D000860:Hypoxia / Q000378:metabolism*; D008297:Male; D009249:NADP / Q000096:biosynthesis; D009504:Neutrophils / Q000166:cytology / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D013481:Superoxides / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D013481:Superoxides; D009249:NADP; D010100:Oxygen