[Age-related features of expression of melatonin and its receptors in myocardial tissues in patients with dilated cardiomyopathy.].

In recent years, more and more attention of researchers has been paid to the study of dilated cardiomyopathy (DCMP). The prevalence of this disease in older age groups is higher than previously thought, and the course of the disease is associated with a worse prognosis and treatment difficulties. Researchers are considering various signaling molecules whose expression changes are associated with myocardial damage and the development of DCMP; evaluation of changes in the expression of melatonin and its receptors in DCMP requires further study. The aim of the study was to study the age-related features of the expression of melatonin and its receptors (MT1, MT2) in the myocardium and their changes depending on the presence of dilated cardiomyopathy. Immunocytochemical and immunohistochemical methods were used to evaluate the expression of melatonin and its MT1, MT2 receptors in myocardial autopsy material and cardiomyocyte cultures of people of different ages with and without cardiovascular pathology. The study revealed age-associated changes in the form of a decrease in the expression of melatonin and its MT1 and MT2 receptors in the myocardium. In individuals with DCMP of all age groups, a more significant decrease in expression was noted: melatonin by 1,6-1,7 times in old age and 3,2 times in old age; MT1 by 1,8 and 2 times, respectively; MT2 by 1,4 and 4 times, respectively. The relationship between the decrease in the expression of melatonin and its receptors in myocardial tissues with age and the presence of DCMP was revealed. The data obtained allow us to clarify age-dependent changes in melatonin and its receptors, as well as to assume their important role in the development of DCMP, which requires further study.