The results of research conducted in the last decade testify to the leading role of the vascular endothelium in the regulation of the work of the cardiovascular system, the dynamics of the state of the vascular wall, and the regulation of vascular functions. The intima of vessels provides a dynamic balance between vasodilating and vasoconstrictive factors, regulates the growth and proliferation of subendothelial cells and non-cellular structures, affects vascular permeability [1]. Endothelial cell dysfunction is a characteristic feature of vascular disease and is characterized by a decrease in angiogenic potential and bioavailability of nitric oxide (NO), impaired vasodilation and increased inflammation [2]. The main role in vasodilation belongs to NO [3].
Research in recent years in the field of vascular physiology has shown that the NO molecule, which is synthesized by the vascular endothelium, has a wide range of bioregulatory effects. NO is an unstable short-lived molecule with a half-life of 2-30 seconds, followed by transformation into nitrite and nitrate and excretion in the urine. Both an excess and a deficiency of NO can be significant in the pathogenesis of many diseases, if we take into account its important role in the regulation of the activity of all cells, organs and systems and the vital activity of the organism as a whole in normal and pathological. Despite the enormous physiological importance of NO, the concentration dependence of its activity, basal concentrations, and how its levels fluctuate during certain pathological conditions [4], such as obesity and hypertension - the main components of metabolic syndrome remain unknown [5].
It is believed that vascular endothelium dysfunction plays a leading role in the formation and progression of hypertension. If in adults the issue of the regulatory influence of NO in hypertension is sufficiently studied, in pediatrics it remains open.