Morphological manifestations of hereditary hypertrophic cardiomyopathy in W/SSM rats

A W/SSM strain of rats with hereditary hypertrophic cardiomyopathy has been created by inbreeding Wistar rats selected for an increased, sensitivity to the cataractogenic effect of high doses of galactose. It is shown that myocardial hypertrophy attended by a diffuse stroma collagenization, focal sclerotic changes, and signs of, chronic heart failure spontaneously develops in these animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 203–207, August, 1994     

Effect of endothelin-1 on DNA synthesis in the myocardium of albino rats during early postnatal ontogeny

Effect of intraperitoneal injection of endothelin-1 on DNA synthesis in the myocardium of newborn albino rats was studied by³H-thymidine autoradiography. Endothelin-1 injected in a single dose of 10 μg/kg stimulated proliferative processes: the index of labeled nuclei and labeling intensity increased. Repeated (5 times) administration of endothelin-1 in doses of 1 and 10 μg/kg increased labeling intensity, but did not change the index of labeled nuclei. The data suggest that endothelins, are involved in morphogenesis of the myocardium during the early postnatal ontogeny. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 12, pp. 623–626, December, 2000     

Inverter mechanism of the influence exerted by insulin on the plasma membranes of cardiac myocytes in rats of different age

In the plasma membranes of cardiac myocytes from old rats, Na, K-ATPase activity and phosphatidylinositol levels were lower and cardiolipin levels higher than in those from younger (adult) animals. Insulin injected into adult rats elevated Na, K-ATPase activity and phosphatidylethanolarnine levels and caused a sharp fall in phosphatidylinositol levels. In old rats, insulin had no effect on Na, K-ATPase activity, but lowered phosphatidylethanolamine levels. In experiments with cellular hybrids (cytosol+plasma membranes), cytosol from adult rats activated Na, K-ATPase in both adult and old rats, whereas cytosol from old rats failed to activate the enzyme both in old and in adult rats. Actinomycin D prevented the stimulatory effect of insulin on Na,K-ATPase activity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 122–125, August, 1995     

Effect of hydra morphogen peptide on the structure of the tissue components of the myocardium layers in the early development of heart hypertrophy in rats

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 115, N ^o 3, pp. 307–309, March, 1993     

Dynorphin administered to Newborn rats modulates morphogenesis of the heart

Proliferation, activity of the nucleolar organizer region, and protein content in cardiomyocytes were studied in 21-day-old rats intraperitoneally treated with κ-opioid receptor agonist dynorphin A_1–13 in a dose of 100 μg/kg on postnatal days 2–6. The content of catecholamines in the heart and proliferative activity of cardiomyocytes remained unaffected, but the number of nucleoli in cardiomyocyte nuclei and the integral optical density of cardiomyocytes stained with amido black B (protein content) increased. The data suggest that administration of dynorphin to newborn rats considerably modulates morphogenesis of the heart at later terms. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 6, pp. 623–625, June, 2000     

State of the myocardium in rats of a new hypertensive strain

Study of the heart in a new strain of rats with hereditary stress-induced hypertension (NISAG) reveals a complex of structural and functional changes which are analogous to the manifestations of essential hypertension. These changes are shown to be adaptive-compensatory in nature and indicative of limited functional reserves of the hypertrophic myocardium. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 9, pp. 271–273, September, 1996     

Morphological study of the effects of textile-immobilized enzymes on an experimental purulent wound

Morphological changes in an experimental purulent wound in a rat model is studied for application of surgical gauze with immobilized enzymes: trypsin, lysozyme, collitin, or co-immobilized trypsin and lysozyme. Comparison of the times of wound cleansing and healing shows that immobilized enzymes are more effective than native preparations, and the therapeutic effect of gauze with the enzyme complex is higher than that of gauze with individually immobilized enzymes. Morphological studies confirm that immobilized trypsin-lysozyme complex and collitin are the most efficient in hastening and potentiating reparative procevesses in a purulent wound. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o , 9, pp. 323–325, September, 1994     

Effects of angiotensin II on DNA synthesis in the myocardium and epithelial tissues in newborn rats

The effects of angiotensin II on DNA synthesis in the myocardium and epithelial tissues of the skin and intestine were studied in 7-day-old albino rats by autoradiography. Angiotensin II significantly increase the labeling index of the nuclei and labeling intensity in myocardial cells and intensified cell proliferation in epithelial tissues. Thus, angiotensin II stimulates proliferative processes in the myocardium and epithelial tissues of the skin and intestine in newbown rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 12, pp. 643–645. December, 1998     

Morphological peculiarities of juxtaglomerular apparatus of the kidney in rats with hereditary stress-induced arterial hypertension (NISAG rats)

Structure of juxtaglomerular apparatus of the kidney in NISAG rats and morphometric parameters of renin-producing juxtaglomerular, cells of afferent arterioles attest to its activation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 5, pp. 576–579, May, 1999     

Resistance of the myocardium to adrenalin in rats adapted to hypoxia

The intensity of the changes produced by adrenalin in the myocardium of rats adapted to hypoxia was studied after its administration to the intact animal and perfusion of the isolated heart. The changes were revealed by histochemical reactions for succinate dehydrogenase activity and staining for lipids. After intramuscular injection of a cardiotoxic dose of adrenalin (2.0 mg/kg) into adapted rats no damage to the myocardium was found, whereas perfusion of the isolated heart with adrenalin (20 g/ml) caused the formation of micronecroses of the cardiocytes. However, their volume was statistically significantly smaller than in the isolated heart of intact rats under similar conditions. Differences in the sensitivity of the myocardium in vivo and in vitro indicate that the phenomenon of protection of the myocardium against the harmful effects of adrenalin in rats adapted to hypoxia is manifested at the level of the intact organism. The increase in the resistance of the myocardium itself is probably due to an increase in the power of the metabolic systems during adaptation.Department of Pathological Physiology, Patrice Lumumba Peoples' Friendship University. Department of Geographic Pathology, Research 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. 84, No. 9, pp. 265–268, September, 1977.     

Peculiarities of the effect of parathyroid hormone on the relaxation of rat myocardium

Contraction of rat myocardium is recorded in a regime of physiological loading that simulates the function of the intact myocardium. Addition of parathyroid hormone accelerates relaxation of the rat myocardium in the control solution and in a solution containing norepinephrine or high calcium concentrations. In a regime of isometric loading the addition of parathyroid hormone inhibits relaxation. At a low Ca concentration in the medium, parathyroid hormone has no effect on the rate of relaxation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 4, pp. 410–413, April, 1996 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences     

Increased resistance to heat shock of isolated hearts from rats adapted to moderate physical exercise

Hearts isolated from rats adapted to physical activity through moderate regular exercise (swimming) were more resistant to heat shock than hearts from unadapted controls. Thus, 15-min perfusion of control hearts with a solution heated to 42°C significantly depressed contraction amplitudes and caused a contracture amounting to 36% of the initial contraction amplitude, as well as increased release of creatine kinase into the perfusate. In the hearts from adapted rats, contraction amplitude was, on average, 2.3-fold greater and the contracture 3.2 times less marked than in the control animals; the test and control hearts did not differ significantly in the release of creatine kinase. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 256–258, March, 1995 Presented by S. S. Debov, Member of the Russian Academy of Medical Sciences     

Morphological study of somatic muscles in alimentary-toxic paroxysmal myoglobinuria

The development of acute focal metabolic lesions of somatic muscles is shown in alimentary-toxic paroxysmal myoglobinuria. Two principal universal reactions of striated muscles are traced in the genesis of this pathological process, namely, contracture damage and intracellular myocytolysis. The functional asynchronism and structural-metabolic heterogeneity of muscle fibers are reflected in the stagewise and typical heterogeneity of the morphological picture, which preserves the entire spectrum of stereotypical pathological reactions regardless of the severity of the illness. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 228–233, February, 1996 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Cytological changes in the myocardium of rats adapted to high-altitude hypoxia

During adaptation of rats to high-altitude hypoxia evidence of stimulation of both formative and lytic processes was observed, and either one process or the other was predominant in different cells. The ratios between volumes of mitochondria and myofibrils were substantially unchanged. The relative volume of the microcirculation was increased on account of dilatation of the small vessels with no increase in their number.Laboratory of Pathomorphology, Institute of Cytology and Genetics, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 11, pp. 1380–1382, November, 1976.     

Phosphoinositide response and alterations in free-radical oxidation in rats with catecholamine-induced cardionecrosis

Vascular spasm, hypertrophy of cardiac muscle cells, and necrotic changes in the myocardial tissue of rats administered norepinephrine in incremental doses over 14 days were accompanied by a considerable activation of lipid peroxidation and a weakening of antioxidant defense during the first 7 days of exposure to this injurious agent. On day 14, despite the greatly increased load of norepinephrine, the concentrations of lipid peroxidation products and the activity of antioxidant enzymes deviated from their control values to a lesser extent than on day 7. A similar change was shown by the concentration of brain tissue phosphatidylinositol-4,5-diphosphate, a source of second messengers, suggesting that the phosphoinositide system of second messengers is involved in the mechanisms whereby the destructive effects of norepinephrine are mitigated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 137–139, August, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Immunocytochemical detection of the nonfibrillary stage of amyloid formation in the mouse myocardium

An indirect electron-microscopic immunoperoxidase method, with pure rabbit antibodies against fibrillary protein of mouse amyloid, was used to study casein amyloidosis in mice. In the early stages of development of amyloidosis deposits of finely granular material appeared in the mouse myocardium. These deposits contained an antigen similar to the fibrillary antigen of amyloid, but were without its fibrillary ultrastructure. The results of this investigation point to the existence of an early nonfibrillary stage of amyloid formation.Laboratories of Electron Microscopy and General Pathological Anatomy, 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. 85, No. 5, pp. 620–623, May, 1978.     

Morphological characteristics of the brain in 20–21-day-old rat embryos and in 1–5-day-old rats

Translated fromByulleten' Experimental'noi Biologii i Meditsiny, Vol. 116, N ^o 12, pp. 641–642, December, 1993     

Detection of reserpine-like substances in the myocardium of animls and man

Substances similar in some of their physicochemical properties to reserpine were found in the myocardium of animals and man. The tissues of the myocardium were shown to synthesize these substances from formate and tryptophan.Laboratory of Pathological Anatomy, All-Union Cardiological Science Center, Academy of Medical Sciences of the USSR. Instite, of Cosmic Research, Academy of Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR E. I. Chazov). Translated from Byulleten' Éksperimental'noi, Biologii i Meditsiny, Vol. 84, No. 7, pp. 35–38, July, 1977.