Effect of Latrunculin B on F-actin content and on CFTR dependent chloride efflux in HBE, CFBE and CFBE/sNHERF1 cells. (A) Summary of F-actin content measurements performed in HBE, CFBE and CFBE/sNHERF1 cells, before and after treatment with the depolymerizing agent Latrunculin B (10 μM). (B) Summary of CFTR-dependent chloride effluxes performed in the three cell lines, before and after treatment with 10 μM Latrunculin B. CFTR-dependent chloride transport was calculated from the difference in alterations of Frsk-stimulated fluorescence measurements in the absence and presence of 5 μM CFTR inhibitor, CFTRinh-172. Each bar represents the mean ± s.e. ***P<0.001; **P<0.01.