In vivo measurement of flow-mediated vasodilation in living rats using high-resolution ultrasound

摘要

In humans, endothelial vasodilator function can be quantified by monitoring FMD, the dilation of conduit arteries in response to physiologically relevant increases in wall shear stress (WSS) induced by ischemic dilation of the downstream microvasculature (2, 13, 20). Increases in WSS, i.e., the tangential force exerted by the flow of blood over the surface of the endothelium, lead to a rapid activation of endothelial nitric oxide (NO) synthase (NOS) with consecutive increases in NO formation (21). Accordingly, FMD is believed to be largely abolished following NOS inhibition and therefore has been used to provide a "read out" of local vascular NO availability.