Fig. 7.
Flagellin- and IL-1β-stimulated ICl is inhibited by p38 blocker. ICl was measured across Calu-3 cell monolayers ([Cl−] gradient conditions) during treatments with S. typhimurium flagellin (10−7 g/ml, apical and basolateral) or IL-1β (10 ng/ml, apical and basolateral) + SB-202190 (1 μM, apical and basolateral). A: typical experiments showing effects of SB-202190 added before or after flagellin. Dark (top) ICl trace shows flagellin increased ICl slowly, and subsequent addition of SB-202190 inhibited the response. The light (bottom) trace shows that adding SB-202190 alone had no effect on ICl, and there was only a small effect of subsequent treatment with flagellin on ICl. Inset: typical experiment (of 5 similar) showing effect of forskolin followed by SB-202190 on ICl. B: typical experiments showing effects of SB-202190 added before or after IL-1β. Dark (top) ICl trace shows IL-1β increased ICl slowly, and subsequent addition of SB-202190 inhibited the response. The light (bottom) trace shows that pretreatment with SB-202190 slowed and reduced the effect of IL-1β on ICl compared with the control. C and D: summaries of effects of flagellin (C) or IL-1β (D) ± SB-202190 on ICl. Bars show average (±SD) ΔICl measured during treatment with flagellin/IL-1β and flagellin/IL-1β+SB-202190 (for 3 experiments like those in the top, dark traces in A and B) or with SB-202190 and SB-202190+flagellin/IL-1β (for 3 experiments like those in the bottom, light traces in A and B). Changes in ICl were calculated as the difference between ICl measured at the beginning in the control condition and ICl measured in the steady state during treatment with flagellin/IL-1β, flagellin/IL-1β+SB-202190, or SB-202190+flagellin/IL-1β. *Significantly different from flagellin or IL-1β (P < 0.05). ΔICl during SB-202190 were not significantly different (P > 0.05) from controls.