Inflammatory and Epithelial Responses in the Nose and Paranasal Sinuses of Experimental Animals

INTRODUCTION Inflammatory responses and toxicant-induced nasal lesions in laboratory animals generally exhibit characteristic, site-specific, distribution patterns (1-4). For example, formaldehyde induces lesions in rats that are essentially confined to the anterior nose, in regions lined by transitional and respiratory epithelia. In contrast, the nasal damage induced by methyl bromide is confined to the olfactory epithelium, and the transitional and respiratory epithelia are not affected. Each nasal toxicant appears to exhibit its own characteristic pattern of lesion distribution.