Abstract
The purpose of this study was the effect of epithelium damage on mechanical responses of airway smooth muscles under different resting tension. We performed acetylcholine (ACh) (10-5M)-induced contraction on tracheal strips from 30 rabbits in five groups (0.5, 1, 1.5, 2 and 2.5 g) before and after epithelium removal. At low resting tension (0.5-1.5g), the epithelium removal decreased the ACh-induced contractions. At 2g resting tension, the epithelium removal increased the ACh-induced contractions of airways with intact epithelium about 20%. At 2.5 g resting tension, the elevation of contraction is about 25% (