Figure 6. Overexpresssion of cofilin, LIMK and occludin, but not claudin-1, significantly diminishes the capsaicin-induced decrease in TER.

(A,B) Transfectant monolayers were prepared in transwell inserts, exposed to 300 µM capsaicin, and subjected to TER measurements. Values represent mean ± S.D. Asterisks indicated significant difference from Vector control at the same time point; *, p<0.01; **, p<0.001. (C) TER was assessed in MDCK monolayers pretreated with vehicle control or 50 µM TFP for 30 min, and exposed to 100 µM capsaicin at time 0. Values represent mean ± S.D. Repeated measure ANOVA followed by Tukey’s multiple comparisons test; **p<0.01, control vs. capsaicin; ^##p<0.01, TFP + capsaicin vs. capsaicin. Each experiment was performed with at least two different clones and repeated at least twice. (D) MDCK monolayers were treated with vehicle or 50 µM TFP for 30 min followed by 100 µM capsaicin for 15 min, then fixed and stained with rhodamine-phalloidin to detect F-actin alteration (upper panel). To see the relative distribution of F-actin (red) in 3D, images labeled with anti-claudin-1 (green) and Hoechst (blue) are also shown below. Images from each z-section were deconvoluted and overlayed. Bar: 10 µm.