OZONE DIFFERENTIALLY MODULATES AIRWAY RESPONSIVENESS IN ATOPIC VERSUS NONATOPIC GUINEA PIGS
Source: Inhalation Toxicology, Volume 14, Number 5, 1 May 2002 , pp. 431-457(27)
Publisher: Informa Healthcare
Abstract:While acute exposures to ozone (O3) can alter airway responsiveness, effects from long-term exposures at low concentrations are less clear. This study assessed whether such exposures could induce nonspecific hyperresponsiveness in nonatopic (nonsensitized) guinea pigs and/or could exacerbate the pre-existing hyperresponsive state in atopic (sensitized) animals, and whether gender was a factor modulating any effect of O3. Responsiveness was measured during and following exposures to 0.1 and 0.3 ppm O3 for 4 h/day, 4 days/wk for 24 wk in male and female nonsensitized animals, those sensitized to allergen (ovalbumin) prior to initiation of O3 exposures, and those sensitized concurrently with exposures. Ozone did not produce hyperresponsiveness in nonsensitized animals, but did exacerbate hyperresponsiveness to both specific and nonspecific bronchoprovocation challenges in sensitized animals, an effect that persisted through at least 4 wk after exposures ended. Gender was not a factor modulating response to O3. Induced effects on responsiveness were not associated with numbers of eosinophils in the lungs nor with any chronic pulmonary inflammatory response, but were correlated with antigen-specific antibodies in blood. This study supports a role for chronic O3 exposure in the exacerbation of airways dysfunction in a certain segment of the general population, namely, those demonstrating atopy.
Document Type: Research Article
Affiliations: 1: Department of Environmental Medicine, New York University School of Medicine, Tuxedo, New York, USA 2: Department of Pharmacology, University of Minnesota, Duluth, Minnesota, USA 3: Department of Pediatrics, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
Publication date: 2002-05-01