title: VO2 kinetics in supra-anaerobic threshold constant tests allow the visualization and quantification of the O2 saving after cytochrome c oxidase inhibition by aerobic training or nitrate administration.
abstract: We tested whether the known cytochrome c oxidase (COX) inhibition by nitric oxide (NO) could be quantified by VO(2) kinetics during constant load supra-Anaerobic Threshold (AT) exercises in healthy trained or untrained subjects following aerobic training or nitrate administration. In cycle ergometer constant load exercises supra-AT, identified in previous incremental tests, VO(2) kinetics describe a double exponential curve, one rapid and one appreciably slower, allowing the area between them to be calculate in O(2) l. After training, with increased NO availability, this area decreases in inverse ratio to treatment efficacy. In fact, in 11 healthy subjects after aerobic training for 6-7 weeks, area was decreased on average by 51 %. In 11 untrained subjects, following the assumption of an NO donor, 20 mg isosorbide 5 mononitrate, area was decreased on average by 53 %. In conclusion, supra-AT VO(2) kinetics in constant load exercises permit the quantification of the inhibitory effect NO-dependent on COX after either physical training or nitrate assumption.
authors.affiliation: Medical and Surgical Sciences Department, S. Orsola-Malpighi University Hospital, Bologna, Italy. claudio.borghi@unibo.it.
authors.forename: D
authors.initials: D
authors.lastname: Maione
authors.forename: A Fg
authors.initials: AF
authors.lastname: Cicero
authors.forename: S
authors.initials: S
authors.lastname: Bacchelli
authors.forename: E
authors.initials: E
authors.lastname: Cosentino
authors.forename: D
authors.initials: D
authors.lastname: Degli Esposti
authors.forename: R
authors.initials: R
authors.lastname: Senaldi
authors.forename: E
authors.initials: E
authors.lastname: Strocchi
authors.forename: S
authors.initials: S
authors.lastname: D'Addato
authors.forename: C
authors.initials: C
authors.lastname: Borghi
mesh_terms: D000328:Adult; D000368:Aged; D015308:Anaerobic Threshold / Q000187:drug effects / Q000502:physiology*; D003576:Electron Transport Complex IV / Q000037:antagonists & inhibitors*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009566:Nitrates / Q000494:pharmacology*; D009569:Nitric Oxide / Q000378:metabolism*; D010100:Oxygen / Q000032:analysis / Q000378:metabolism*; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology*; D012016:Reference Values
chemical_list: D009566:Nitrates; D009569:Nitric Oxide; D003576:Electron Transport Complex IV; D010100:Oxygen