The endothelial glycocalyx (eGC), a mesh of anionic biopolymers covering the luminal surface of endothelial cells, is increasingly considered as an intravascular compartment that protects the vessel wall against pathogenic insults. Although central to the pathophysiology of vascular barrier dysfunction in cardiovascular disease, eGC damage has been generally understudied, mainly because of its degradation during tissue handling. We have previously shown that nanomechanics (thickness and stiffness) of the eGC on living endothelial cells can be measured by a mechanical nanosensor, mounted on an atomic force microscope. Here, we hypothesized that atomic force microscopy (AFM) can be used to quantify damage of the eGC in established animal models of acute and chronic vascular inflammation - namely endotoxemia and chronic renal failure. AFM reliably depicted a marked reduction of aortic eGC thickness (266.4 ± 27.1 vs. 136.7 ± 32.2 nm, PE. coliLPS i.v.) compared to controls (n=4 per group). Similarly, AFM revealed that aortic eGC thickness (381.6 ± 134.4 vs. 132.2 ± 26.9 nm, P<0.001) and stiffness (0.34 ± 0.07 vs. 0.22 ± 0.02 pN/nm, P