THE USE OF VARIOUS MATERIALS AND METHODS FOR ASSESSMENT THE STATE OF THE ENDOTHELIUM IN SCIENTIFIC RESEARCH
Authors: Gayova І. M. , Tymkiv I. V. , Blyzniuk M. V. , Neyko V. E. 
Published: January 2025

Endothelial functioning is one of the key topics of theoretical and practical medicine. Endothelial dysfunction (or endothelial dysfunction, ED) is understood as an imbalance of vasoconstriction/vasodilation, which occurs due to changes in the release of vasoactive biological substances (hormones, mediators, growth factors). The role of ED in hypertension, atherosclerosis, other vascular lesions is being studied. Methods for determining ED are divided into two groups: the first includes invasive and non-invasive methods for studying vascular tone in conditions of altered blood flow (this includes ultrasound, angiography), the second group is the study of the content, concentrations of circulating markers. Analysis of the literature showed that there are no new research methods in this matter yet. Atherosclerosis is a clinical manifestation of ED and the prevalence of this pathophysiological condition is extraordinary. There are numerous works where attempts are made to analyze the patterns of changes in the endothelium, and therefore vasoconstriction/vasodilation in various experiments: in animals and in humans; on vessels of different diameters; patients were chosen for all ages, healthy, with monopathology or with comorbid conditions. Dopplerography has proven a decrease in flow-dependent dilation as one of the reliable criteria for ED. Numerous works are devoted to the role of lipid peroxidation in the development of ED, among the markers of atherogenesis initiation are the products of free-radical oxidation of proteins in serum, the products of free-radical oxidation of proteins in lipoproteins, diene conjugates in platelets, malonic dialdehyde. Disturbances in the hemoglobin system due to activation of free-radical oxidation in red blood cells correlate with metabolic indicators such as glutathione peroxidase, superoxide dismutase, reduced glutathione, which are predictors of  ED. An important role of nitric oxide (NO) in the regulation of the functional state of the endothelium has been proven, increased activity of NO-synthetase leads to an increase in the content of nitric oxide, which is confirmed by an increase in the level of its metabolites in the blood. Studies have established the relationship of the blood coagulation system and the state of the endothelium: an increase in the level of Willebrand factor reflects the state of the endothelium in patients with coronary artery disease. Insufficiency of sex hormones is named among the factors that provoke changes in the functioning of the endothelium. Conclusions on humoral factors: increased levels of adhesion molecules (VCAM-1S), insulin-like growth factor (IGF-1), aldosterone content in arterial hypertension confirm endothelial dysfunction. Using the radioimmune method, it is proved that in older people less vasodilators and more vasoconstrictors are synthesized by the endothelium. A separate group of studies is the study of ED patterns in various diseases, in particular, following data are available: endothelial dysfunction suggests a complicated course of chronic obstructive pulmonary disease against the background of coronary heart disease. Thus, damage to the endothelium by lipid peroxidation products, violation of the balanced synthesis of vasoactive factors by the endothelium worsens its protective properties, makes it sensitive to the effects of damaging factors, disrupts the wall homeostasis and promotes atherogenesis.