title: 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.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Jichi Medical School, Tochigi, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ohta
authors.forename: Minako
authors.initials: M
authors.lastname: Takanosawa
authors.forename: Chiori
authors.initials: C
authors.lastname: Matumoto
authors.forename: Nobuko
authors.initials: N
authors.lastname: Makino
authors.forename: Shinichi
authors.initials: S
authors.lastname: Ishimoto
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ichimura
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects*; D003907:Dexamethasone / Q000008:administration & dosage / Q000494:pharmacology*; D005938:Glucocorticoids / Q000008:administration & dosage / Q000494:pharmacology*; D007150:Immunohistochemistry; D007279:Injections, Subcutaneous; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D009831:Olfactory Mucosa / Q000166:cytology / Q000187:drug effects*; D051381:Rats; D013997:Time Factors
chemical_list: D000893:Anti-Inflammatory Agents; D005938:Glucocorticoids; D019394:Ki-67 Antigen; D003907:Dexamethasone