The study of the microcirculatory channel of the connective tissue of the myocardium of the ventricles improves the understanding of the features of pathological processes, such as ischemia, hypoxia and remodeling of the myocardium, the evaluation of the effectiveness of drug therapy, as well as rehabilitation methods. The purpose of the study is to determine the changes in the hemomicrocirculatory channel of the ventricular myocardium in triptorelin-induced central deprivation of the synthesis of luteinizing hormone and the correction of this condition by the introduction of quercetin. The experiment was conducted on 60 sexually mature white male rats weighing 140-160 g. The rats were divided into 3 groups. 1 group – control, rats injected with physiological solution (10 animals). Group 2 – rats that were injected subcutaneously with diphereline (triptorelin embonate) at a dose of 0.3 mg of the active substance per kg of body weight for 365 days (25 animals). Group 3 – rats that were injected with a solution of triptorelin at the rate of 0.3 mg of the active substance per kg of body weight to simulate central deprivation of the synthesis of luteinizing hormone with the addition of quercitin to the diet using a gastric tube based on the body weight of the animals three times a week (25 animals). Animals were withdrawn from the experiment after 1, 3, 6, 9 and 12 months by overdose with ether anesthesia. A comprehensive study of histological preparations of the myocardium and quantitative calculation of the diameter of the vessels of the microcirculatory bed were carried out using a light microscope with a digital microfilter and software adapted for these studies. Statistical processing of the research results was carried out using the Microsoft Office Excel software and the Real Statistics 2019 extension. When analyzing the index of arteriole diameters in the group of animals that were injected with triptorelin after 1, 3, 6, 9 and 12 months, a significant increase in the diameter of arterioles was established compared to the control group animals, respectively, by 13.9 % – 40.8 % – 102.6 % – 112.6 % – 11.5 %; and in animals to which quercetin was administered against the background of triptorelin administration, it was established that this indicator after 1 month did not reliably differ from the similar one in the control group, and after 3, 6, 9 and 12 months it was reliably higher than in the control respectively by 11.5 % – 136.2 % – 101.1 % – 101.4 %. The analysis of the diameters of the venular link of the hemomicrocirculatory channel in the group of animals administered triptorelin showed a significant increase in the value of this indicator after 3, 6, 9 and 12 months compared to the control group, respectively by 20.0 % – 71.2 % – 57.8 % – 22.9 %; and in animals that were additionally injected with quercetin after 1 month, the diameter of venules was significantly reduced by 8.1% compared to the control, and after 3, 6, 9 and 12 months – respectively by 5.2 % – 87.5 % – 64.0 % – 50.4 % it was significantly greater than in control animals. Analysis of capillary diameters in the group of animals administered triptorelin showed a significant increase in the value of this indicator after 1, 3, 6 and 9 months compared to the control group, respectively by 23.9 % – 49.1 % – 61.8 % – 36.7 %; and in animals that were additionally injected with quercetin, the capillary diameter significantly increased compared to the control after 3, 6, 9, and 12 months – by 22.3 % – 55.3 % – 17.1 % – 25.2 %, respectively. The conducted study showed that the introduction of triptorelin leads to structural and functional changes in the components of the microcirculatory channel of the myocardium of the ventricles of the heart, which are characterized by changes in the diameter of the arterial and venous links with a gradual increase in blood flow, the maximum of which is at the 6th month of the experiment in both experimental groups, but without impaired outflow in the group with the addition of quercitin.
