Endothelial barrier function and capillary permeability mechanisms

Endothelial barrier function and capillary permeability mechanisms refer to the physiological processes that regulate the exchange of fluids, solutes, and cells between the blood vessels and surrounding tissues. This barrier is primarily maintained by the endothelial cell layer, which utilizes specialized structures such as tight junctions (e.g., claudins, occludin) and adherens junctions (e.g., VE-cadherin) to control paracellular transport. Dysregulation of these mechanisms is a hallmark of various pathological conditions, including systemic inflammation, sepsis, and chronic diseases like diabetic retinopathy, where excessive permeability leads to tissue edema and organ dysfunction. While not a single molecular target, this system is modulated by numerous signaling pathways, most notably the VEGF and Angiopoietin/Tie2 axes. Therapeutic intervention often focuses on stabilizing these junctions or inhibiting pro-permeability factors to restore vascular integrity and prevent fluid leakage.

Other names

Endothelial barrierVascular permeabilityCapillary permeabilityEndothelial semi-permeability

Drugs typically target specific signaling pathways that regulate the barrier, such as inhibiting Vascular Endothelial Growth Factor (VEGF) to reduce permeability or using corticosteroids to stabilize tight junctions and reduce inflammatory cytokine-mediated leakage.