Nitrogen dioxide-induced eosinophilia and mucosal injury in the nose of the guinea pig.
Nitrogen dioxide exposure-induced mucosal pathology of the guinea pig nose was studied. Guinea pigs were exposed to 3 ppm or 9 ppm of nitrogen dioxide for 6 h a day, 6 times weekly for 2 weeks, and sacrificed 24 h after the final exposure. Exposure to 3 ppm of nitrogen dioxide resulted in decreased ciliary activity and slight eosinophil accumulation on the epithelium and submucosal layer. More serious pathologies were observed in the nose of guinea pigs exposed to 9 ppm of nitrogen dioxide, including a more prominent eosinophil influx to the epithelium and epithelial injury due to activation of eosinophils. Epithelial damage induced by nitrogen dioxide could lead to hyperresponsiveness and may result in a prolonged allergic inflammation. Our study suggests that environmental nitrogen dioxide may contribute to hyperresponsiveness and thus be involved in the increased morbidity of allergic rhinitis.
Ohashi
Y
Y
Department of Otolaryngology, Osaka City University Medical School, Japan.
Nakai
Y
Y
Sugiura
Y
Y
Ohno
Y
Y
Okamoto
H
H
Tanaka
A
A
Kakinoki
Y
Y
Hayashi
M
M
D000818:Animals; D002923:Cilia / Q000187:drug effects / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D004802:Eosinophilia / Q000139:chemically induced* / Q000473:pathology; D005260:Female; D006168:Guinea Pigs; D008854:Microscopy, Electron; D009297:Nasal Mucosa / Q000187:drug effects* / Q000648:ultrastructure; D009585:Nitrogen Dioxide / Q000633:toxicity*; D011897:Random Allocation; D013997:Time Factors
D009585:Nitrogen Dioxide