Skip to main content
. Author manuscript; available in PMC: 2013 Jan 1.
Published in final edited form as: Microvasc Res. 2011 May 20;83(1):31–44. doi: 10.1016/j.mvr.2011.05.004

Figure 5. PAR1 signaling inducing FAK activity and reversible disruption of endothelial barrier function.

Figure 5

Upon ligation of PAR1 by thrombin, the Gα subunit of the heterotrimeric G protein dissociates from Gβγ. Gαq increases intracellular Ca2+ concentration, which increases endothelial permeability by activating MLCK and RhoA. RhoA also induces FAK activation. FAK negatively regulates RhoA-GTP by activating p190RhoGAP, thus turning off endothelial cell contraction. Gβγ mediates activation of FAK through Fyn kinase leading to interaction of FAK with p120-catenin that facilitates re-annealing of adherens junction and thereby restores normal barrier function. Inset shows the release of Gβγ from RACK1/Gα complex upon thrombin stimulation.