[Comparison between repeated antigen and acetylcholine-induced bronchoconstriction in development of airway wall thickness in a chronic guinea pig model of asthma].
Asthma is associated with a chronic remodeling of the airways, but it remains to be elucidated whether repeated bronchoconstriction (BC) influences any structural attributes of the lungs. To investigate the role of repeated BC on the morphology of the airways, we chronically exposed guinea pigs to an aerosol of acetylcholine (ACH) over a period of 6 months. The guinea pigs were challenged with either ACH or saline daily for 10 days and thereafter were challenged once a week. To compare repeated BC with a chronic model of allergic inflammation, an additional group of animals were sensitized to aerosolized ovalbumin (OA) and subsequently exposed with OA. The airway wall area and basement membrane (BM) thickness were measured by standard morphometric techniques. Both airway wall area and BM thickness were significantly increased in OA exposed guinea pigs compared with both saline control and AHC-exposed guinea pigs. Our results suggest that persistent bronchoconstriction and/or allergic airway inflammation in asthmatics may contribute to the thickness of the airway wall observed in this disorder. However, repeated acute bronchoconstriction events may not contribute to the increase in the airway wall or BM thickness.
Nakano
Y
Y
Department of Pulmonary Medicine and Clinical Immunology, Dokkyo University School of Medicine.
Toda
M
M
Yoshida
M
M
Sagara
H
H
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D000941:Antigens / Q000276:immunology*; D001249:Asthma / Q000276:immunology / Q000473:pathology*; D001980:Bronchi / Q000473:pathology*; D016084:Bronchoconstriction / Q000502:physiology*; D006168:Guinea Pigs; D008297:Male; D010047:Ovalbumin / Q000276:immunology
D000941:Antigens; D010047:Ovalbumin; D000109:Acetylcholine