Figure 2. Effect of elevated cAMP on the distribution of ZO-1 and cadherins. Cells were treated with TNF-α (T) for 6 h and where indicated were co-treated with 10 µM forskolin (F) and 50 µM rolipram (R). A-D: Distribution of ZO-1. In untreated cells (Control, A), the ZO-1 is contiguous at the cell-cell border (shown by arrows). It is undisturbed by F and R (B). Exposure to TNF-α (C) induced dispersion of ZO-1 (shown by arrows), which was opposed by co-treatment with F and R (D). E-H: Pan-cadherins at the focal plane of AJC. In untreated cells (Control, E), localization of cadherins at the region of cell-cell contacts is intense (shown by arrows). Upon treatment with F and R (F), the distribution of cadherins is unaltered. Exposure to TNF-α (G) resulted in reduced intensity of cadherins at the cell border as well as sporadic disengagement (shown by arrows). Co-treatment with F and R (H) prevented the TNF-α response. All the images shown are representative of at least three independent experiments.