Mechanotransduction and Vascular Remodeling
Blood vessels respond to pressure and flow, more exactly to hoop stress and wall shear. In the short term, a pressure increase results in a smooth muscle contraction and thus in a diameter decrease, so that hoop stress normalizes (myogenic response, see Chap. 19). A flow increase implies an increase in wall shear stress, which is sensed by the endothelium (glycokalix). The endothelium liberates smooth muscle dilators (e.g., NO), and an increase in diameter results which reduces the wall shear stress: Flow Mediated Dilation. In the long term, a sustained high blood pressure implies a high wall hoop stress leading to wall thickening (hypertrophy), and normalization of hoop stress. Increased flow gives increased wall shear stress and leads to increase in vessel diameter. In general, vascular remodeling leads, within limits, to a restoration to control levels of hoop stress and wall shear stress.
KeywordsZero stress state Classification of remodeling Glycokalix Myogenic response Flow mediated dilation
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