Uptake of BrdU in olfactory and respiratory epithelium of rabbits with experimental sinusitis

Sinusitis was induced in six rabbits in order to evaluate its influence on the proliferation of cells in the olfactory epithelium compared with the re spiratory epithelium during conservative antibiotic therapy. Then 1% ofloxa cin was injected into the paranasal sinuses. Three normal rabbits were not administered any treatment and served as controls. The rabbits were sacrifi ced under intravenous anesthesia and the olfactory and respiratory mucosa w as excised 24 hours after intravenous administration with the labeling reag ent 5-bromo-2'-deoxyuridine (BrdU). The extent of cell proliferation in the se tissues was estimated by immunohistochemical staining with BrdU-specific antibody. The uptake of BrdU was significantly increased (p = 0.0099) in t he respiratory mucosa, but not in the olfactory mucosa. Furthermore, in olf actory epithelium, 79.2% and 16.7% of all BrdU-positive cells were olfactor y and basal, respectively. Thus, turnover of epithelial cells due to sinusi tis was not as accelerated in the olfactory mucosa as in the respiratory mu cosa during antibiotic treatment.