TOPICAL CORTICOSTEROIDS POTENTIATE MUCIN SECRETION IN THE NORMAL NOSE

The exact mode of action of topical nasal corticosteroids is still unc ertain. The aim of this study was to determine their effects on microv ascular permeability and cellular and glandular secretion by measuring the levels of total protein, albumin, lysozyme and mucin recovered in nasal lavage fluid before and after 3 weeks of treatment with a topic al nasal corticosteroid in 12 normal non-atopic subjects. Six subjects applied 200 mu g fluticasone propionate and six applied 200 mu g becl omethasone dipropionate to one nostril in each 24 h: matched placebo w as applied to the other nostril. There was a significant rise in the l evel of mucin recovered compared with baseline values following flutic asone administration (baseline 76.2 mu g/ml (mean) +/-5.5 (SEM), fluti casone 118.3 mu g/ml+/-11.6 P = 0.015) and beclomethasone administrati on (baseline 64.3 mu g/ml+/-6.6, beclomethasone 87.2 mu g/ml+/-4.8, P = 0.041). There was no significant change in the levels of total prote in, albumin or lysozyme following either active medication or placebo treatment. Topical corticosteroids appear to potentiate mucin secretio n and do not alter serous secretion or microvascular permeability in t he unchallenged non-atopic nose.