title: Histopathologic and morphometric evaluation of the nasal and pulmonary airways of cats with experimentally induced asthma.
abstract: BACKGROUND
  Allergic rhinitis frequently occurs as a comorbid condition in asthmatic people, suggesting that the upper and lower airways may be immunologically linked. Our research group has developed an experimental aeroallergen model of asthma in cats. We hypothesized that aeroallergen sensitization and challenge would induce morphologic changes in the nasal airways of cats that mimic those observed in the bronchial airways.
  
  
  METHODS
  Five mixed breed cats were sensitized to Bermuda grass allergen and then serially challenged with aerosolized Bermuda grass allergen to induce an asthmatic phenotype. Four control cats were similarly treated with saline vehicle. Nasal tissues and lungs were processed for histopathological and morphometric analyses.
  
  
  RESULTS
  Eosinophilic inflammation, epithelial hypertrophy and mucous cell metaplasia were observed along the pulmonary axial airway mucosa of allergen-sensitized (asthmatic) cats. Mild eosinophilic inflammation was observed in the nasal airways of asthmatic cats. This alteration was confined primarily to the anterior nasal cavity, resulting in an increase in tissue eosinophils at this site compared to controls (p < 0.05). A marked increase in tissue mast cells was observed throughout all regions of the nasal airways of asthmatic cats compared to control cats (p < 0.05). There was no difference in intraepithelial mucosubstances between the nasal airways of controls and asthmatic cats. There was no correlation between upper and lower airway eosinophils or mast cells.
  
  
  CONCLUSIONS
  Cats with experimentally induced asthma exhibit morphologic changes in the nasal airways that are distinct from the alterations observed in the lungs. These results are similar to those observed in people with comorbid asthma and allergic rhinitis.
authors.affiliation: Department of Small Animal Clinical Sciences, Michigan State University College of Veterinary Medicine, D208 Veterinary Medical Center, East Lansing, MI 48824, USA.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Venema
authors.forename: Kurt J
authors.initials: KJ
authors.lastname: Williams
authors.forename: Laurel J
authors.initials: LJ
authors.lastname: Gershwin
authors.forename: Carol R
authors.initials: CR
authors.lastname: Reinero
authors.forename: Stephan A
authors.initials: SA
authors.lastname: Carey
mesh_terms: D000485:Allergens / Q000008:administration & dosage / Q000276:immunology; D000818:Animals; D001249:Asthma / Q000276:immunology* / Q000473:pathology; D016535:Bronchial Hyperreactivity / Q000276:immunology* / Q000473:pathology; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002415:Cats; D031744:Cynodon / Q000276:immunology; D004804:Eosinophils / Q000276:immunology; D008168:Lung / Q000276:immunology / Q000473:pathology; D008407:Mast Cells / Q000276:immunology; D009297:Nasal Mucosa / Q000276:immunology* / Q000473:pathology; D020545:Respiratory Mucosa / Q000276:immunology* / Q000473:pathology; D012137:Respiratory System / Q000276:immunology* / Q000473:pathology; D065631:Rhinitis, Allergic; D012221:Rhinitis, Allergic, Perennial / Q000276:immunology / Q000473:pathology
chemical_list: D000485:Allergens