Abstract
Many epidermiological studies have demonstrated a close relationship between air pollution and the increasing number of patients with allergic disease. We have attempted to determine if increased airway permeability induced by air pollution could be one of the pathogenic factors leading to nasal hypersensitivity.
The penetration of horseradish peroxidase (HRP) into nasal mucosa was examined electron microscopically after transtracheal instillation in 66 guinea pigs. HRP was instillated immediately, 15, 30 min., 1, 2 and 4 hr after exposure of 1 ppm ozone for 1 hour. Nasal membrane were surgically obtained and electron microscopic examination was performed. In the control group, a very small amount of HRP was taken up by endocytosis and HRP did not penetrate the epithelium. In the ozone exposed group, however, a large amount of HRP was taken up into the epithelium and HRP penetrated into cell junctions, which was not observed in controls. Some of the tight junctions were found to be “leaky”. Increased permeability was observed as long as 2 hours after ozone exposure.
These findings suggest that permeability of nasal membrane increases after ozone exposure and that this mechanism might lead to easy penetration of allergens into nasal epithelium.
