title: Pulmonary sensitivity to ozone exposure in sedentary versus chronically trained, female rats.
abstract: Epidemiological data suggest that a sedentary lifestyle may contribute to increased susceptibility for some environmental toxicants. We developed an animal model of active versus sedentary life style by providing female Sprague-Dawley rats with continuous access to running wheels. Sedentary rats were housed in standard cages without wheels. After training for 12 wks, rats were exposed to 0, 0.25, 0.5 or 1.0 ppm ozone [O3 for 5 h/d, 1 d/wk, for 6 wk (N = 10 per group)]. Body composition (%fat, lean and fluid) was monitored noninvasively over the course of the study. Ventilatory parameters [tidal volume, minute ventilation, frequency and enhanced pause (Penh)] were assessed using whole-body plethysmography prior to O3 and 24 h after the 5th O3 exposure. Trained rats lost ∼2% body fat after 12 wk of access to running wheels. Peak wheel activity was reduced by 40% after exposure to 1.0 ppm O3. After the 5th O3 exposure, body weight and %fat were reduced in sedentary but not trained rats. Penh was significantly elevated in sedentary but not trained rats the day after exposure to 1.0 ppm O3. However, lung lavage cell counts and biomarkers of pulmonary inflammation measured 1 day after the final exposure were inconsistently affected by training. Wheel running led to marked physiological responses along with some indication of improved pulmonary recovery from O3 exposure. However, wheel running with O3 exposure may also be a detriment for some pulmonary endpoints. Overall, a sedentary lifestyle may increase susceptibility to O3, but additional studies are needed.
authors.affiliation: a Toxicity Assessment Division , Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park, NC , USA .
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Gordon
authors.affiliation: a Toxicity Assessment Division , Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park, NC , USA .
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Phillips
authors.affiliation: a Toxicity Assessment Division , Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park, NC , USA .
authors.forename: Tracey E
authors.initials: TE
authors.lastname: Beasley
authors.affiliation: b Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development , U.S. Environmental Protection Agency , Research Triangle Park, NC , USA , and.
authors.forename: A
authors.initials: A
authors.lastname: Ledbetter
authors.affiliation: c Department of Physiology , Faculty of Veterinary Medicine, University of Uludag , Bursa , Turkey.
authors.forename: Cenk
authors.initials: C
authors.lastname: Aydin
authors.affiliation: b Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development , U.S. Environmental Protection Agency , Research Triangle Park, NC , USA , and.
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: Snow
authors.affiliation: b Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development , U.S. Environmental Protection Agency , Research Triangle Park, NC , USA , and.
authors.forename: Urmila P
authors.initials: UP
authors.lastname: Kodavanti
authors.affiliation: a Toxicity Assessment Division , Office of Research and Development, U.S. Environmental Protection Agency , Research Triangle Park, NC , USA .
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Johnstone
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D001823:Body Composition; D001835:Body Weight; D005260:Female; D009043:Motor Activity / Q000187:drug effects; D010126:Ozone / Q000633:toxicity*; D010993:Plethysmography, Whole Body; D017207:Rats, Sprague-Dawley; D012119:Respiration / Q000187:drug effects; D057185:Sedentary Behavior
chemical_list: D000393:Air Pollutants; D010126:Ozone
keywords: Air pollution; body composition; exercise; fat loss; obesity