The effect of hydrogen peroxide on smooth muscle tone, mucus secretion and epithelial albumin transport of the ferret trachea in vitro

Abstract

The effect of hydrogen peroxide (H 2O 2) was examined on baseline and on methacholine- and phenylephrine-stimulated smooth muscle tone, mucus volume and lysozyme outputs, and epithelial albumin transport of the ferret whole trachea in vitro. H 2O 2 (10 μM–10 mM) had no significant effect on tracheal smooth muscle tone but produced concentration-dependent increases in mucus volume, lysozyme and albumin outputs. The potential difference (P.D.) across the trachea was not changed by H 2O 2. Exposure of the trachea to H 2O 2 (1 mM) for 2 h reduced the smooth muscle contractions and lysozyme outputs due to methacholine (1 μM) and phenylephrine (10 μM). Methacholine-induced albumin output was significantly increased by H 2O 2 but that due to phenylephrine was not significantly affected. Exposure to H 2O 2 had no significant effect on the mucus volume output produced by methacholine or phenylephrine. Thus H 2O 2 directly stimulates submucosal gland secretion, including secretion from serous cells, and epithelial albumin transport across the ferret trachea but has no effect on tracheal smooth muscle tone. H 2O 2 reduces methacholine- and phenylephrine-induced smooth muscle contractions and serous cell secretion. H 2O 2 causes hyperresponsiveness of albumin output to methacholine but not to phenylephrine.