Immunohistochemical Analysis of MMP-2 Expression in the Myocardium During the Postinfarction Period.

Immunohistochemical analysis revealed 2.5-fold increased of expression MMP-2 in myocardium samples during the early period (up to 3 days) of postinfarction reparative regeneration. During this period, MMP-2 was detected mainly in monocytes/macrophages circulating in the blood and migrating to the necrotic zone, while expression in the intermuscular and perivascular connective tissue was lower.

Morphological Evaluation of Oxidative Phosphorylation System in Myocardial Infarction under Conditions of Modified Vascular Endothelial Growth Factor Concentration.

The relationship between vascular endothelium growth factor (VEGF) and cardiomyocyte oxidative phosphorylation level in experimental myocardial infarction, caused by diathermocoagulation of the periconical ventricular artery, was studied by immunofluorescent microscopy. Staining showed uneven distribution of cytochrome c in the mitochondria in the focus of myocardial infarction 2 h after the operation. After 24 h uneven staining of cardiomyocytes was found in the peri-infarction zone and no staining in the zone of myocardial infarction.

Mitral and Aortic Valvulitis in Primary Chronic Septic Endocarditis.

Results of long-term prospective follow-up of patients with early stages of mitral and aortic valvulitis and primary chronic septic endocarditic are presented. Clinical diagnostics of the diseases is described and the key role is assigned to pathognomic (absolute) clinical symptoms. The tendency to progressive fibrosis of endocardial structures with subsequent gradual development of valve dysfunction and stenosis (especially for the mitral valve) is revealed.

Content of circulating extracellular DNA, plasma activities of matrix metalloproteinases, and ultrastructure of the myocardium in hypothyroid rats with hypercholesterolemia.

Free circulating extracellular DNA, plasma activities of matrix metalloproteinases in hypothyroid rats, and ultrastructural changes in the myocardium were studied under conditions of experimental hypercholesterolemia. For suppression of thyroid function, the animals received antithyroid drug mercazolyl under conditions of cholesterol diet. Hypercholesterolemia in hypothyroid rats (thyroxine concentration 2-fold below the normal) was paralleled by a pronounced increase of the concentration of free circulating extracellular DNA and total matrix metalloproteinases 2 and 7 activity.

Proliferative activity of cadriomyocytes in chronic hypercholesterolemia.

We studied proliferative activity of cardiomyocytes (using proliferation marker Ki-67) and compared it with their total number in the heart under conditions of experimental chronic hypercholesterolemia and its combination with hypothyroidism. It was found that Ki-67-positive cells are primarily located in the subepicardial layer near the heart base in both intact and experimental animals. Replicative cardiomyocyte pool in intact rats constituted 1.