Dynamics of the DNA concentration in heart muscle cell nuclei of rats with experimental myocardial infarction

The DNA concentration was determined microspectrophotometrically in heart muscle cell nuclei of rats at different stages of experimental myocardial infarction. In the intact rat heart some nuclei (1.5–1.8%) of myocytes had a tetraploid DNA complement. Myocardial infarction activates the polyploidization of the nuclei of the muscle cells, especially these lying around the area of injury. The highest intensity of polyploidization of the muscle nuclei was found during the first week of myocardial infarction. Later during the experiment the degree of ploidy of the myocytes increased.Central Pathological Anatomical Laboratory, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 3, pp. 366–368, March, 1977.     

Substrate supply to the heart during myocardial infarction: selectivity and time course of utilization of metabolites

Myocardial infarction is experimentally modeled in rabbits. The blood content of metabolites in intact and experimental animals is measured at different times of infarction. An inverse utilization of the substrates by the myocardium is found: an enhanced utilization of glucose and reduced utilization of fatty acids. The emergence of metabolic acidosis and of an arrhythmogenic effect, and the aggravation of ischemia are substantiated by the accumulation of oxaloacetate, pyruvate, lactate, glycerophosphate, and dihydroxyacetone phosphate. During the repair period a tendency toward a normalization of substrate utilization by the myocardium is noted. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No. 6, pp. 621–624, June, 1995 Presented by T. T. Berezov, Member of the Russian Academy of Medical Sciences     

Changes in gluco- and mineralocorticoid adrenal functions in spontaneously hypertensive rats during experimental myocardial infarction

The dynamics of corticosterone and aldosterone contents during the acute and restoration periods of experimental myocardial infarction was studied in Wistar and spontaneously hypertensive rats. In spontaneously hypertensive rats, the increase in aldosterone concentration during the acute period was followed by elevation of corticosterone content, which attested the disadaptive course of experimental myocardial infarction against the background of hereditary arterial hypertension. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 1, pp. 25–27, January, 2000     

Effect of malaben on catecholamine content in organs of animals with experimental myocardial infarction

The content of adrenalin and noradrenalin was determined in tissues of the heart, adrenals, spleen, and brain of rats with experimental myocardial infarction. A considerable fall in the tissue catecholamine level was found. Malaben restores the normal catecholamine content in the tissues in myocardial infarction, posibly as a result of the antihitamine properties of the compound.Department of Pharmacology, Leningrad Institute of Pharmaceutical Chemistry. (Presented by Academician of the Academy of Medical Sciences of the USSR S. V. Anichkov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 7, pp. 49–51, July, 1977.     

Effect of preliminary adaptation to transauricular electrostimulation on the content of catecholamines and met-enkephalin in rat heart and adrenals in stress and acute myocardial infarction

Adaptation to transauricular electrostimulation decreases the content of epinephrine in the adrenal glands and norepinephrine in the heart. Immobilization stress has no appreciable effect on the content of catecholamines in the heart and adrenal glands. In animals with myocardial infarction, the content of norepinephrine in the heart decreases 2-fold, while the content of epinephrine in the adrenals decreases inconsiderably. Adaptation to transauricular electrostimulation is associated with a rise in met-enkephalin concentration. Preadaptation induces a more pronounced rise of met-enkephalin and promotes normalization of epinephrine in the adrenals, without changing the content of norepinephrine in the heart. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 10, pp. 388–391, October, 1997     

Relations between myeloid and stromal cells of bone marrow in acute experimental aplasia

Acute hypoplasia of the hematopoietic system was produced in guinea pigs by injecting vinblastin in a dose of 0.1 mg/100 g body weight intraperitoneally either once or twice at an interval of 7 days. The number of myelokaryocytes and the concentration (per 10⁵ myelokaryocytes) and total number (per femur) of precursors of fibroblasts were determined in the femora by the fibroblast colony method. After injection of the cytostatic the decrease in number of myelokaryocytes was accompanied by a change in the concentration of stromal precursors per femur. It is postulated that the response of the bone marrow during hypoplasia is determined by interaction between the myeloid and stromal cells.Clinical Hematology Laboratory, Institute of Pediatrics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR M. Ya. Studenikin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 211–214, February, 1977.     

Proliferative activity of cardiomyocytes and specific features in the course of acute experimental myocardial infarction in rats with chronic alcohol poisoning

Vascular mesenchymal changes are less expressed in rats preexposed to alcoholization, and the fibrillogenesis associated with these changes occurs later and is less severe. In rats suffering myocardial infarction in the presence of chronic alcohol poisoning the proliferative activity of cardiomyocytes is reduced. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 172–174, February, 1994 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Quantitative morphological analysis of acute focal damage and myocardial infarction

Some approaches based on polarization microscopy and stereology are proposed for quantitative evaluation of acute dystrophic and necrotic lesions in the myocardium. It is shown that in sudden death and myocardial infarction the degree III contractures predominate in cardiomyocytes, while lumpy degradation of myofibrils under these conditions is half as often. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 1, pp. 112–115, January, 1998     

Activity of lysosomal apparatus in rat myocardium during experimental coronary and noncoronary myocardial damage

Cardiac and plasma activities of marker lysosomal enzymes were studied in Wistar rats with metabolic (epinephrine) and occlusion (ligation of coronary arteries) myocardial infarction. Activity of all examined lysosomal enzymes significantly increased in the myocardium and blood plasma starting from the first day after ligation of the coronary arteries and was accompanied by leukocytic infiltration of the myocardium. Enzyme activity gradually decreased to postoperation day 14. In metabolic infarction leukocytic infiltration and specific activity of lysosomal enzymes rose gradually and attained maximum to postoperation day 14, while the signs of labilization of lysosomal membranes appeared from the first postoperation day. Plasma activity of lysosomal enzymes in metabolic infarction increased smoothly and peaked on day 14. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 6, pp. 626–628, June, 2000     

Pharmacokinetics of antipyrin,nifedipine, and diazepam in experimental myocardial infarction

Novosibirsk Medical Institute. Laboratory of Clinical and Experimental Lymphology, Siberian Branch, Academy of Medical Sciences. (Presented by Academician Yu. I. Borodin, Academy of Medical Sciences.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 4, pp. 381–383, April, 1992.     

A comparative study of the effects of dimebon,obsidan, finoptin,and cordaron on the functional state of ischemic focus and size of necrotic zone in experimental myocardial infarction

Dimebon, an antihistamine agent, exerts a moderate antianginal effect, improving the function of ischemic focus in the myocardium and decreasing the necrotic zone in experimental myocardial infarction. Dimebon is less active than obsidan, finoptin (except for the size of the necrotic zone), and cordaron. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 12, pp. 642–644, December, 1996     

The Mast cell system and blood coagulation in mountain dogs with myocardial infarction

A comparative study of the responses of the mast cell and coagulation systems to experimentally induced myocardial infarction in dogs that had been constantly living at a medium altitude (1600 m above sea level) and those constantly living at a low altitude (760 m) revealed less marked morphological and functional changes in these systems in the former (“mountain”) dogs, which may be interpreted as an indication of their enhanced nonspecific resistance acquired as a result of long-term adaptation to conditions prevailing at medium altitudes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 580–583, June, 1994 Presented by K. V. Sudakov, Member of the Russian Academy, of Medical Sciences     

A preliminary course of transauricular electrostimulation mitigates impairment of cardiac contractile function in rats with myocardial infarction

A course of transauricular electrostimulation (TES) consisting of 10 sessions was administered to rats before the induction of myocardial infarction by Selye's method and to rats that were left intact. In the latter anirnals, the electrostimulation did not influence cardiac contractile function at rest (as judged by heart rate, developed pressure, and Katz's index), but exerted beneficial chronotropic and inotropic effects during the maximum isometric tension produced by compression of the ascending aorta. In the TES-pretreated rats with a 2-day-old myocardial infarct, cardiac contractile function was depressed significantly less, both at rest and during isometric tension, than in infarcted rats not exposed to TES. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 568–571, December, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Effect of uridine derivatives on myocardial stunning during postischemic reperfusion of rat heart

Uridine and uridine-5’-monophosphate prevent myocardial stunning during postischemic reperfusion of isolated rat heart. Uridine-5’-diphosphate does not prevent postischemic myocardial dysfunction, while uridine-5’-triphosphate aggravates it. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 10, pp. 411–414, October, 2000     

Rhythmic changes of morphometric parameters of rat cardiac scar connective tissue

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 115, N ^o 2, pp. 213–214, February, 1993