MORPHOLOGICAL CHARACTERISTICS OF THE ENDOCRINE FUNCTION OF THE HEART IN COMORBID PATHOLOGY

OBJECTIVE

Aim: To study the ultrastructural remodeling of atrial myoendocrine cells (AMC) of the atrial myocardium in streptozotocin-induced diabetes (SID) under chronic immobilization stress (CIS).

PATIENTS AND METHODS

Materials and methods: 40 sexually mature white male rats (body weight 150-180 g) were included in the study. Four groups were formed: group 1 - animals with comorbid pathology (SID and CIS), group 2 - animals with SID, group 3 - animals with CIS, group 4 - intact animals.

RESULTS

Results: On the 14th day of the development of SID and CIS, an increase in the functional activity of AMC is noted, which is confirmed by hyperplasia and hypertrophy of the protein-synthesizing apparatus, an increase in the volume density of secretory granules (SG), especially diffusing ones, and indicates enhanced release of atrial natriuretic peptide (ANP) from cells during the experiment. On the 56th day of the experiment, in groups 1 and 2 of , destructive changes in AMC were noted, such as vacuolar and balloon dystrophy, colliquative and partial necrosis. At the same time, the functional activity of AMC of different regions of the myocardium significantly. In animals with CIS, the volume density of young and diffusing SG in AMC is decreased.

CONCLUSION

Conclusions: Therefore, in the early stages of the development of SID and CIS, an increase in the morpho-functional activity of AMC is noted. The long course of SID and its combination with CIS lead to destructive changes in AMC and to decrease in their secretory activity.

THE PECULIARITIES OF BIOCHEMICAL AND MORPHOLOGICAL CHANGES IN THE HEART OF THE CASTRATED RATS IN THE DEVELOPMENT OF ADRENALIN DAMAGE OF HEART

OBJECTIVE

The aim of the study was to evaluate the state of oxidation processes and morphological changes in the heart of castrated rats during the development of epinephrine heart damage (EHD).

PATIENTS AND METHODS

Materials and methods. The study was performed on 120 white male Wistar rats. The animals were divided into four series: 1 - control, 2 - castration. For EHD, rats were injected once intraperitoneally with a 0.18% solution of adrenaline hydrotartrate at the rate of 0.5 mg/kg of weight. Castration was performed under anesthesia. The concentration of diene and triene conjugates (DC, TC), Schiff's bases (SB), TBA-active products (TBA-ap), oxidatively modi"ed proteins (OMP), activity of superoxide dismutase (SOD) and catalase (CAT) were determined in the heart. A morphological study of preparations stained with Azantrichrome was carried out. All studies were performed in control, 1, 3, 7, 14 and 28 days after adrenaline injection.

RESULTS

Results: In the I series DC and TC increased after 1 day of EHD, fell to control values after 3 days, and then had wave-like character (highest - after 14 days). SB decreased (minimal after 7 days), TBA-ap increase (maximal after 14 days). OMP370 increased after 1 and 3 days, after 7 days they did not differ from the control, after 14 days they were higher than in control, and after 28 days they decreased to the control values. OMP430 and OMP530were greater than the control indicators in all terms, except the last; the maximum was noted after 14 days. The activity of antioxidant enzymes was lower than the control indicators at all times of the study. Castration caused an increase of lipid peroxidation. After 7 days, DC and TC, were lower and SB - higher, than in the I series. Castration caused a decrease in OMP. In EHD all values of OMP, compared to the castrated control rats, were higher at all studed times Castration leads to increase of SOD, and decrase of CAT. All indicators of SOD and CAT exceeded the indicators of animals of the I series at all times of the study. Biochemical changes are consistent with morphological changes. After injection of epinephrine, severe vascular disorders, adventitia edema, perivasal edema, endothelial cell damage, dilatation of hemicapillaries, full blood vessels, stasis, hemorrhages in the surrounding tissues, and sclerosing of the walls of arteries and venules were observed. Cardiomyocytes were swollen, shortening, necrosis was observed, myocytolysis was noted. Edema of the stroma was noted. In the stroma, around the vessels, located cells of connective tissue elements were observed. Indicate more damage to the myocardium in the process of development of EHD in animals of the I series.

CONCLUSION

Conclusions: Castration of rats causes an increase of lipid peroxidation products and CAT activity in the heart, but a decrease in the content of OMP. Adrenaline injection causes activation of lipid peroxidation and an increase in the content of OMP. During the development of EHD, the activity of antioxidants is significantly higher in II group. Biochemical changes are consistent with morphological, and indicate more damage to the myocardium in the development of EHD in animals of the I series.

Medical and social issues of cardiovascular diseases and their solution based on the experimental study of myocardial fibrosis

OBJECTIVE

Introduction: The prevalence and incidence of cardiovascular diseases have been attracting considerable attention in recent decades. This is partly due to the fact that myocardial fibrosis is the major consequence of the most nosological units of cardiovascular diseases. We believe that early pathogenic therapy of myocardial fibrosis should be taken into consideration as a solution to this issue. The change of the connective tissue metabolism in myocardium is the central chain in pathogenesis of diffuse ischemic necrotic cardiosclerosis (DINC) occurs after repeated epinephrine injury of myocardial tissues. The aim: The present study establishes that use of metabolic therapy by trimetazidine (TM) has a protective effect on myocardium repeatedly damaged by epinephrine in hight concentration during the development of DINC in rats with different resistance to hypoxia.

PATIENTS AND METHODS

Materials and methods: Using the method of hypobaric hypoxia, male albino rats were divided into three groups due to their different resistance to hypoxia. Each group was divided into four equal subgroups: control group, DINC group (2 times repeated injections of epinephrine hydrotartrate (0,5 mg/kg body weight) and calcium gluconate (5 mg/ kg body weight), control group introdused with trimetazidine dihydrochloride (10 mg/kg body weight), DINC treated with TM group (2 times repeated injections of epinephrine hydrotartrate (0,5 mg/kg body weight) and calcium gluconate (5 mg/kg body weight) group introduced with TM (10 mg/kg body weight) for all period of observation. The concentration of protein-bound oxyproline in homogenate of myocardium was determined at 7, 14 and 30 days after the modelling pathology and the histological examination of Masson trichrome staining of myocardium was performed.

RESULTS

Results: Experimental modeling of DINC increased the concentration of protein-bound oxyproline in homogenate of myocardium at 7, 14 and 30 days after the modelling pathology, as well as accompanied by metabolic imbalances in diffuse connective tissue elements, which are rich in collagens. Experimental modeling of DINC+TM increased the concentration of protein-bound oxyproline in blood serum significantly less intensive.

CONCLUSION

Conclusions: The intensity of metabolic imbalances in diffuse connective tissue elements of myocardium is the highest in the low resistant animals to hypoxia. Those results are confirmed by histological examination of the myocardium of rats with different resistance to hypoxia. Fibrotic regions in myocardium are rich in collagens. It has been revealed that the most pronounced therapeutic effect of TM is observed in animals with low resistance to hypoxia, slightly less - in animals with medium resistance to hypoxia, and the lowest - in animals with high resistance to hypoxia.