Fig. 6.

Gelsolin peptide prevented increases in airway resistance in response to escalating doses of inhaled methacholine. A: confirmation of the penetration of rhodamine B-conjugated peptides in peripheral airways. Representative mouse lung histology 30 min after nebulization of gelsolin peptide or PBS via a tracheostomy. B: costaining with a smooth muscle marker SM22 alpha (green) showed localization of rhodamine B-conjugated peptide (red) overlapping with the green signal. White arrow indicates airway smooth muscle layer. C: inhalation of control or gelsolin peptide itself did not affect central airway resistance (Rn) compared with PBS inhalation (n = 8–9 mice in each group, ANOVA with Bonferroni comparison). D: following inhalation of a control peptide or gelsolin peptide, A/J mice were exposed to increasing concentrations of methacholine via nebulization. An increase in Rn in response to an escalating dose of methacholine was significantly attenuated in mice pretreated with the gelsolin peptide compared with mice pretreated with the control peptide. n = 6–9 (up to 25 mg/ml dose) and n = 3–5 (up to 37.5 mg/ml dose), *P < 0.05, Mann-Whitney.