Fig. 3. Activation of Rap1 in endothelial cells induces cell-cell junction maturation. Anti-VE-cadherin and F-actin staining of HUVE cells treated for 30 minutes with vehicle or the Epac-specific cAMP analog 007. Stimulation with 007 clearly increased cell-cell junction maturation: the adherens junctions form a smoother line between the cells. Endothelial cell permeability is reduced as a biological consequence of the junction tightening (Bar, 10 µm).