Endothelium-dependent regulation of the cardiovascular system.

Vascular endothelial cells play an important role in modulating cardiovascular function, by liberating several vasoactive substances, such as prostacyclin, endothelium-derived relaxing factor/nitric oxide, a hyperpolarizing substance, and vasoconstrictor substances. Their roles in the cardiovascular system include modulation of the contraction of the underlying vascular smooth muscle, interaction between blood components and blood vessel wall, vascular growth, as well as regulation of the cardiovascular system at several levels beyond the vascular wall. Alterations in the endothelial functions and the related processes are now known to be involved in the pathogenesis of many cardiovascular diseases, including hypertension and atherosclerosis. Thus, the impaired endothelial regulation of the cardiovascular system may have an important implication for the development and progression of many cardiovascular diseases.