The endothelial glycocalyx (EG), a complex hair-like structure attached to the surface of the
endothelium, is primarily composed of proteoglycans and glycosaminoglycans. Positioned to
sense shear stress caused by blood flow, the EG transforms these mechanical forces into
biochemical responses through a mechanism known as mechanotransduction. This study,
utilizing pressure myography, focuses on the key role of the endothelial EG in endothelial
functions, particularly in mechanotransduction.
We explored two endothelium-dependent signaling pathways activated in the presence of
shear stress or vasodilators, i.e. the nitric oxide (NO) and endothelium-derived
hyperpolarization (EDH) pathways. Visualization of the EG was performed by confocal
microscopy, after immunolabeling of sialic acid and n-acetylglucosamine residues using
fluorescent wheat germ agglutinin (WGA). This approach also allowed the quantification of
EG degradation after sheddases treatments.
The results confirm a more pronounced contribution of the NO pathway to ACh-induced
vasodilation in carotid arteries, while the EDH pathway predominates in mesenteric arteries.
Conversely, when it comes to flow-mediated dilation, the EDH pathway prevails in both
carotid and mesenteric arteries. Furthermore, the degradation of the EG in mouse mesenteric
arteries, by sheddases induces strong and significant decreases in EDH-dependent vascular
responses, underscoring the crucial role of the EG in regulating endothelial function.
Functional and morphological approach to the endothelial glycocalyx in mice carotid and mesenteric arteries
MARY, L. (Auteur). 15 janv. 2024
Student thesis: Master types › Master en sciences biologiques