Antigen-induced airway hyperresponsiveness and pulmonary inflammation in allergic dogs

J Appl Physiol (1985). 1985 Apr;58(4):1347-53. doi: 10.1152/jappl.1985.58.4.1347.

Abstract

We studied whether antigen-induced airway hyperresponsiveness was associated with pulmonary inflammation in 11 anesthetized ragweed-sensitized dogs. Airway responsiveness to acetylcholine aerosol was determined before and at 2, 6, and 24 h after ragweed or sham aerosol challenge. Pulmonary inflammation was assessed by bronchoalveolar lavage (BAL) performed at either 2 or 6 h. Total pulmonary resistance increased 11-fold at 5 min after ragweed. Airway responsiveness was unchanged at 2 h but was increased 6.6-fold at 6 h in 8 of 11 dogs (P less than 0.001); hyperresponsiveness persisted from 4 days to 4 mo. Airway responsiveness was unchanged by aerosols of diluent. Neutrophils in BAL fluid increased approximately sixfold at 2 h (P less than 0.02) and at 6 h (P less than 0.02) after antigen challenge. There were fewer eosinophils in fluid recovered at 6 h after antigen compared with 2 h lavages (P less than 0.05). In three nonresponders, BAL showed no significant changes in neutrophils and eosinophils after antigen. Thus antigen-induced hyperresponsiveness is associated with the presence of pulmonary inflammation, presumably arising from the airways and involving both neutrophils and eosinophils.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acetylcholine / immunology*
  • Animals
  • Bronchi / pathology
  • Bronchial Provocation Tests
  • Cell Count
  • Dogs
  • Lung Compliance
  • Pneumonia / chemically induced*
  • Pulmonary Alveoli / pathology
  • Respiratory Hypersensitivity / immunology*
  • Respiratory Hypersensitivity / pathology
  • Therapeutic Irrigation

Substances

  • Acetylcholine