ИСТИНА

Red blood cells (RBCs) are the primary cellular elements of blood performing several important functions in the body. RBCs are able to reversibly aggregate form 2D or 3D structures (aggregates), which significantly influence the blood circulation in the body. Studying the aggregation properties of erythrocytes is an essential task because it can provide insight into the state of blood and its ability to effectively transport oxygen. Aggregation properties of erythrocytes can change due to various factors, such as alterations in the protein composition of blood and diseases. Investigating age-related changes in RBCs aggregation properties is an important task in assessing blood microcirculation. The main goal of this work is to study the aggregation properties of erythrocytes in patients of different age groups suffering from arterial hypertension (AH) and atrial fibrillation (AF). Measurements of RBCs microrheological parameters were conducted using the erythrocyte aggregometer RheoScan. The following parameters were determined based on the signal of diffuse light scattering from blood samples: the critical shear stress (CSS) - the minimum shear stress that must be applied to the flow of aggregates in order to break them down, and the aggregation index (AI) - the fraction of cells that aggregate within the first 10 seconds of the process of spontaneous aggregation. The results of the conducted research showed that the aggregation parameters, including the aggregation index and the critical shear stress, vary depending on the age of donors in all groups of participants, and these differences are statistically significant (p < 0.05). The study was completed with financial support within the framework of the Development Program of the Interdisciplinary Scientific and Educational School of Moscow University “Photon and Quantum Technologies. Digital medicine". Digital medicine" (project No. 23-Ш06-03).