Antioxidant consumption and repletion kinetics in nasal lavage fluid following exposure of healthy human volunteers to ozone.
To obtain information on the real-time events occurring within human respiratory tract lining fluids (RTLFs) during ozone exposure, sequential nasal lavage was performed on 13 human volunteers exposed on separate occasions to 0.2 parts per million O3 and filtered air (2-h exposures, with intermittent exercise).
Nasal lavage was performed and blood samples obtained at four time points throughout each exposure : pre-exposure (Pre-E), 1 h into exposure (1h-E), immediately post-exposure (0h-PE) and 1 h post-exposure (1h-PE).
Endobronchial mucosal biopsies were obtained at 1.5 h-post exposure (1.5 h-PE).
Nasal RTLF neutrophilia was not apparent during, or 1.5 h after, O3 exposure.
Furthermore, activation of the pre-existing neutrophil population did not occur.
Airway permeability was not altered by this O3 exposure regimen.
Sequential lavage resulted in significant washout of RTLF ascorbic acid, reduced glutathione, extracellular superoxide dismutase and myeloperoxidase at 1h-E, 0h-PE and 1.5h-PE relative to baseline Pre-E values.
In contrast, RTLF uric acid (UA), total protein and albumin concentrations did not display washout kinetics.
Of the antioxidants examined, only UA was clearly depleted by O3, concentrations, falling by 6.22 mumol.
L-1at 1h-E, compared with 1.61 mumol.
L-1 (p<0.01) during control air exposure. (...)
Mots-clés Pascal : Ozone, Exposition, Homme, Consommation, Antioxydant, Exploration, Lavage, Nez, Biopsie, Bronche, Urique acide, Etude expérimentale, Appareil respiratoire
Mots-clés Pascal anglais : Ozone, Exposure, Human, Consumption, Antioxidant, Exploration, Washing, Nose, Biopsy, Bronchus, Uric acid, Experimental study, Respiratory system
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0414207
Code Inist : 002B30A02A. Création : 22/03/2000.