TY - JOUR
T1 - Preexposure to ozone blocks the antigen-induced late asthmatic response of the canine peripheral airways
AU - Turner, Claudia R.
AU - Kleeberger, Steven R.
AU - Spannhake, Ernst W.
N1 - Funding Information:
This study was supported byNIH grant ES03505; Dr. Turner was supported by NIH training grant HL-07534; and Dr. Kleeberger was supported by R23 HL37061. The authors thank Matthew Kovalsky and Terry Adams fortheir valuable technical assistance and Dr. Arthur M. Dannenberg, Jr., forthe use of his histologie facilities. Requests forreprints should besent toDr. E. W. Spannhake, School of Hygiene and Public Health, The Johns Hopkins University, 615 North Wolfe Street, Baltimore, MD 21205.
Copyright:
Copyright 2016 Elsevier B.V., All rights reserved.
PY - 1989/11/1
Y1 - 1989/11/1
N2 - The influence of exposure of the airways to ozone on acute allergic responsiveness has been investigated in several species. Little is known, however, about the effect of this environmental pollutant on the late asthmatic response (LAR) in animals in which it is exhibited. The purpose of this study was to evaluate this effect in the canine peripheral airways and to assess the potential role of mast cells in modulating the effect. A series of experiments on seven mongrel dogs demonstrated that the numbers of mast cells at the base of the epithelial region of small subsegmental airways exposed to 1 ppm ozone for 5 min were significantly (p <.01) increased 3 h following exposure compared to air exposed or nonexposed control airways. In a second series of experiments performed on eight additional mongrel dogs with inherent sensitivity to Ascaris suum antigen, antigen aerosol was administered to the sublobar segment 3 h following ozone preexposure when mast cell numbers were pre-sumed to be increased. These experiments were performed to determine whether ozone preexposure could enhance the late-phase response to antigen by virtue of acutely increasing the number of mast cells available to bind the antigen. Four of the eight dogs tested displayed a late-phase response to antigen following air-sham preexposure. In these four dogs, simultaneous ozone preexposure of a contralateral lobe completely blocked the late-phase response to antigen. These results indicate that the consequences of a single exposure to ozone persist beyond its effects on acute antigen-induced bronchoconstriction and extend to the complex processes involved with the late response. This attenuating effect of ozone is seen under conditions where mast-cell numbers in the airways are increased above baseline levels.
AB - The influence of exposure of the airways to ozone on acute allergic responsiveness has been investigated in several species. Little is known, however, about the effect of this environmental pollutant on the late asthmatic response (LAR) in animals in which it is exhibited. The purpose of this study was to evaluate this effect in the canine peripheral airways and to assess the potential role of mast cells in modulating the effect. A series of experiments on seven mongrel dogs demonstrated that the numbers of mast cells at the base of the epithelial region of small subsegmental airways exposed to 1 ppm ozone for 5 min were significantly (p <.01) increased 3 h following exposure compared to air exposed or nonexposed control airways. In a second series of experiments performed on eight additional mongrel dogs with inherent sensitivity to Ascaris suum antigen, antigen aerosol was administered to the sublobar segment 3 h following ozone preexposure when mast cell numbers were pre-sumed to be increased. These experiments were performed to determine whether ozone preexposure could enhance the late-phase response to antigen by virtue of acutely increasing the number of mast cells available to bind the antigen. Four of the eight dogs tested displayed a late-phase response to antigen following air-sham preexposure. In these four dogs, simultaneous ozone preexposure of a contralateral lobe completely blocked the late-phase response to antigen. These results indicate that the consequences of a single exposure to ozone persist beyond its effects on acute antigen-induced bronchoconstriction and extend to the complex processes involved with the late response. This attenuating effect of ozone is seen under conditions where mast-cell numbers in the airways are increased above baseline levels.
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U2 - 10.1080/15287398909531355
DO - 10.1080/15287398909531355
M3 - Article
C2 - 2585540
AN - SCOPUS:0024407660
SN - 0098-4108
VL - 28
SP - 363
EP - 371
JO - Journal of Toxicology and Environmental Health
JF - Journal of Toxicology and Environmental Health
IS - 3
ER -