Abstract
Histamine contents were quantitatively evaluated in the nasal mucosa of toluene diisocianate (TDI)-sensitized guinea pigs, of the experimentally-induced hypersensitivity model, which were treated with or without the topical administration of glucocorticoids. Histamine contents were significantly increased after TDI sensitization for 4 weeks. Treatment with the newly developed glucocorticoid, fluticasone propionate (FP), designed for topical use, tended to normalize the elevated histamine contents. Single applications of TDI caused the rapid reduction of histamine in the nasal mucosa of TDI-sensitized guinea pigs. The reduction of histamine content due to fluticasone application may suggest that several mechanisms, including inhibitions to the accumulation of histamine-containing cells and/or to the reduction of histamine content in each cell and to the reduction of the rate of histamine release from mast cells, might contribute to the clinical efficacy of this glucocorticoid for the treatment of allergic rhinitis.
