The role of focal adhesion kinase, its associated proteins, Rho GTPases, cAMP, angiopoetin-1, and Bbeta15–42 peptide in barrier maintenance. FX06 = Bbeta15–42 peptide, Ang-1 = angiopoetin-1, Prolea = proleakage mediators, Rho = Rho A, FAK = focal adhesion kinase, Gra = GTPase regulator associated with FAK (GRAF), RhoG = 190Rho GTPase activating protein (190RhoGAP), C3 = C3 toxin, N = normal level, Incr = increased level, Rp = Rap-1, PKA = protein kinase A, VASP = vasodilator stimulated phosphoprotein, Barrier str = barrier strengthening, Barrier disr = barrier disruption, solid line = contributing factor, and dashed line = inhibiting factor. Various substances are involved in barrier strengthening/disruption. Some substances have different effects that depend on the presence or the absence of proleakage mediators (normal condition); for instance, Rho contribute to barrier strengthening in normal condition, but contribute to stress fiber formation in the presence of proleakage mediators.
