Schematic illustrating the hypothesized role of the glycocalyx in lung vascular
mechanotransduction. Left: during static conditions, the glycocalyx maintains
barrier function over the intercellular junction. Right: during increased
vascular pressure, the increased hydraulic flow through the glycocalyx deforms
or stresses the glycosaminoglycan (GAG) fibers, which in turn activates
endothelial nitric oxide synthase (eNOS) and leads to barrier dysfunction.
ΔPc, change in capillary pressure; Q, flow; ZO-1 and ZO-2, zonula
occludens-1 and -2; vin, vinculin; VE-Cad, vascular endothelial cadherin; ECM,
extracellular matrix (Adapted from Dull R, Cluff M, Kingston J, Hill D, Chen H,
Hoehne S, Malleske D, Kaur R. Lung heparan sulfates modulate Kfc during
increased vascular pressure: evidence for glycocalyx-mediated
mechanotransduction. Am J Physiol Lung Cell Mol Physiol 2012;302:L816-28).