THE FEATURES OF THE STRUCTURE OF THE LYMPHOID COMPONENT OF RAT PERICARDIUM THROUGHOUT ONTOGENESIS.

Abstract

Introduction. Research of the cardiovascular system is a relevant issue today, because its diseases are highly pathological and significantly affect the general mortality of the population. The morphofunctional state of the heart directly depends on the pericardium, which, in turn, performs a number of key physiological functions for the heart. The pericardium, having a coelomic origin, can perform not only a mechanical barrier function, but also exhibits immune properties through lymphoid tissue associated with serous membranes, known as serosa-associated lymphoid clusters. Objective. The purpose of the study is to expand the understanding of the structure of the lymphoid component of the pericardium, to analyze the qualitative composition of this tissue, and to study the topography at various stages of the postnatal ontogenesis of rats. Materials and methods. The study was conducted on 4 age groups of laboratory rats, each of which included 5 individuals. Film preparations were made. Samples of film preparations were stained with methylene blue, as well as with hematoxylin and eosin natively and after fixation. Results. The lymphoid tissue of the pericardium of rats is mainly represented by small and medium-sized lymphocytes, as well as cells that are similar to plasma cells. Features of the topography of the lymphoid tissue of the pericardium in the early and late postnatal periods, revealed with the help of various staining methods, testify to important aspects of the morphology of the rat pericardium. Conclusions. Analysis of the lymphoid population of cells made it possible to determine them in different parts of the organ during ontogenesis, indicating the presence of dynamic changes in the lymphoid tissue of the pericardium during the postnatal period. Taking into account the age-related features of the structure of the pericardium, further study of the qualitative and quantitative composition of serosa-associated lymphoid clusters in rats is recommended, which allows for a more detailed understanding of the immune processes that occur in this organ. Considering the importance of immunological aspects of the cardiovascular system, the obtained data have a high potential for application in veterinary and medical practice.