Vasomotor Function of Endothelium
Blood vessel endothelium plays a crucial role in the vascular tone maintenance through a whole range of vasoactive substances which it produces in response to various physical and chemical stimuli. Vasomotor disturbances are one of the key elements of endothelial dysfunction. This review contains contemporary data on implementation, regulation and disturbances of endothelial function. Within the framework of this study, vasomotor reactions are regarded as a two-component system with reception of the stimulus by endothelial cells on the first stage and transmission of the relevant signal to smooth muscle cells on the second stage. Special attention is paid to reception of biochemical, local and systemic humoral signals by endothelial cells. The mechanisms of endothelium-dependent vasorelaxation realized by nitric oxide, prostacycline, endothelium-derived hyperpolarizing factors are discussed in a separate section. In the section devoted to vasoconstrictor function of endothelium, we describe physiological and pathological role of endothelin 1 and arachidonic acid metabolites which provide contraction of smooth musculature of vascular wall.