Fig. 4.

Gelsolin (GSN) peptide attenuated methacholine (MCh)-induced peripheral airway constriction, and ryanodine and caffeine pretreatment abolished subsequent relaxation of MCh-induced contraction by GSN peptide. A and B: 8 min after initiation of airway constriction with MCh, peripheral airways were exposed to 10 µM gelsolin or control peptide. Representative micrograph images (top) from the data plotted in tracings (bottom) are shown (1–3). corresponds to airway before stimulation (1: Resting), contraction in response to 300 nM MCh (2: MCh) and airway after peptide application [3: MCh + control (CTL) peptide or GSN peptide]. C: airway relaxation measured at the end of peptide treatment was significantly more in gelsolin peptide-treated airways (n = 8 slices, n = 3 mice for each group). D: when 25 µM ryanodine were applied with 20 mM caffeine to deplete intracellular calcium stores, the subsequent MCh-induced constriction was not reversed by GSN peptide. GSN peptide-induced relaxation was compared between caffeine alone and caffeine plus ryanodine treatment (n = 8–9 slices, n = 3 mice for each group). **P < 0.01, Mann-Whitney.