High-Dose Glucocorticoids Inhibit Proliferation of Rat Olfactory Epithelium

Abstract

Glucocorticoids (GCs) are commonly prescribed for treatment of olfactory dysfunction. However, the effects of GCs on olfactory epithelium are not well known. We investigated the effects of high-dose GCs on proliferating cells of olfactory epithelium. Five adult male rats (300 g) received a single daily subcutaneous dose of vehicle containing 0.3 mg dexamethasone (DEX) for 9 days (DEX+ group), and a control group received vehicle alone (DEX– group). We compared sections from the Two groups for numbers of Ki67-positive cells. The mean number of Ki67-positive cells per 500 olfactory epithelial cells was 9.6 for the DEX+ group and 58 for the DEX– group (significant difference). We conclude that high-dose GC suppressed proliferation of olfactory epithelium. We suggest that high-dose GC suppresses cytokines and growth factors, resulting in secondary suppression of proliferating ability.