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 Printable version |
Adaptation of resistance arteries to chronic changes in blood flow: outcome with respect to age and associated risk factors |
Sang Thrombose Vaisseaux. Volume 23, Number 10, 521-8, Décembre 2011, Mini-revue
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 Résumé
Texte intégral
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Author(s) : Mohamed Lamine Freidja, Daniel Henrion |
Summary : Resistance arteries control local blood flow to organs. They are sensitive to pressure which generates a myogenic contraction and to flow (shear stress) which stimulates the endothelial cells to produce vasodilating agents such as NO. The balance between myogenic tone and flow-mediated dilation determines a basal tone which makes vasoactive neurohumoral local and circulating systems more efficient. This basal tone gives resistance arteries the ability to respond quickly to the needs generated by the metabolic demand of the different organs. Metabolic needs and blood flow can increase chronically during growth, pregnancy and with exercise. A chronic increase in blood flow is also required in ischemic diseases during which flow-mediated arterial remodeling plays a major role in revascularization in addition to arteriogenesis and angiogenesis. Of course, this remodeling is deleterious in the vicinity of tumor tissue. Remodeling induced by a chronic increase in blood flow is associated with increased luminal diameter, wall thickening and improved endothelial function. Nevertheless, the amplitude of this remodeling decreases with age and disappears after the median life expectancy has been attained, resulting in a dramatic increase in the risk of cardiovascular diseases. Targeting this remodeling in physiological and pathological vascular aging might be an alternative therapeutic target. |
Keywords : resistance arteries, blood flow, vascular aging |
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