Adaptation to hypoxia,unlike adaptation to stress,fails to protect the isolated heart from reperfusion after total ischemia (An NMR study)

Effects of adaptation to hypoxia on the contractility of isolated rat hearts and on their levels of ATP and inorganic phosphate after total ischemia were evaluated. This adaptation failed to render the cardiac energy-supplying system more resistant to postischemic reperfusion and thus did not accelerate the restoration of cardiac contractility after ischemia. The results of adaptation to hypoxia were then compared with those of adaptation to stress, which had been shown to bring about a marked increase in cardiac resistance to postischemic reperfusion. It is concluded that the profound differences noted between the cardioprotective effects of these two forms of adaptation are due to a much greater accumulation of stabilizing proteins from the HSP70 family during adaptation to stress. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 11, pp. 481–484, November, 1995 Presented by N. R. Paleev, Member of the Russian Academy of Medical Sciences     

Seasonal differences in the development of heightened resistance of the isolated heart during adaptation to physical exercise

Substantial seasonal differences are found in the development of the cardioprotective effect of adaptation to physical exercise: in winter such adaptation results in an increase of the resistance of the isolated heart to the contracture and arrhythmogenic effects of ischemia and reperfusion, while in summer the anticontracture effect is absent and the antiarrythmic effect is significantly lowered. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 299–301, September, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Spermatogenesis in rats after administration of the anthracycline antibiotic pharmorubicin

It is established that Wistar rat testes demonstrate stable morphological changes attended by a diminishment of the stem cell population, depletion of the other layers of the spermatogenic epithelium, a decrease of the number of tubules with meiosis stage XII, and intensified desquamation of epithelial cells during 30 days after administration of pharmorubicin in the maximal permissible dose. The depletion of the stem cell population may result in long-term damage to the reproductive function and manifest itself long after antibiotic treatment. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 308–310, March, 1995     

Comparative analysis of polypeptides in the heat shock proteins synthesized in the myocardium of Wistar and August rats

The use of two-dimensional electrophoresis to study the polypeptide composition of heat shock proteins 70 synthesized in the myocardium of Wistar and August rats in response to thermal stress and repetitive immobilization stress revealed interstrain differences in the composition of stimulated polypeptides in these proteins. The differences are mainly due to differential expression of the heat shock protein gene(s) encoding polypeptides with pI 6.2–6.0 in the two strains. The drastically reduced levels of the synthesis and/or accumulation of some heat shock proteins 70 in the hearts of August rats are associated with their failure to develop cardioprotective phenomena in response to repetitive immobilization stress. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 30–32, July, 1995 Presented by R. S. Karpov, Member of the Russian Academy of Medical Sciences     

Expression of the c-myc and Ca-ATPase genes in cardiac muscle during adaptation to repeated stress

In the course of adaptation to repeated stress, the expression of the proto-oncogene c-myc found to increase much more rapidly than that of the Ca-ATPase gene. It is suggested that an increase in the level of c-myc expression may activate the structural Ca-ATPase gene and possibly also the heat-shock proteins. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 124–126, February, 1994     

Effect of vagotomy on the feedback inhibition of pancreatic secretion

Chronic experiments on fistulized dogs showed that the pancreatic secretion stimulated by intraduodenal administration of acidified hydrolysine was depressed after bilateral supradiaphragmatic truncal vagotomy, and that the inhibitory influence of exogenous pancreatic enzymes on pancreatic secretion disappeared on postoperative days 10–16. Subsequently, the feedback inhibition of pancreatic secretion was slowly restored, but even 45 days after vagotomy it was still weaker than in intact dogs. It is concluded that the feedback inhibition of pancreatic secretion is centrally controlled from the duodenum via the vagus nerves. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 465–469, May, 1995 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences     

Effect of dexamethasone on the expression of binding sites for high-density lipoproteins in cultured rat hepatocytes (Independence of the hormone effect on the intracellular cholesterol pool)

It is shown that glucocorticoids play a key regulatory role directed toward the maintenance of an optimal level of binding and internalization of HDL₃ in hepatocytes. Their stimulatory effect on the expression of HDL receptors proves to be independent of changes in the CH content in parenchymal cells. Translated fromByulleten' Eksperimentalnoi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 50–53, January, 1994     

Morphofunctional aspects of liver regeneration in experimental correction of toxic hepatitis

It is demonstrated that cytoplasmic extract of rat pup liver stimulates cellular and intracellular regeneration of hepatocytes exposed to the toxic agent CCl₄. Injection of liver cytosol stabilizes lysosomal membranes, increases the coefficient of energy efficiency of mitochondria, and activates proliferation of polyploid hepatocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 656–659, June, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Effect of prenatal hypoxia on DNA synthesis in the tracheal epithelium and LPO-AOD system in the lungs of newborn rats

Newborn rats euthanized 24 h after birth were examined. The rats were born to females exposed to chronic hypobaric hypoxia on days 14–19 of gestation. The index of nuclei labeled with³H-thymidine in the tracheal epithelium of newborn rats exposed to prenatal hypoxia was 3 times lower than in the control. The LPO level was higher in posthypoxic animals than in intact rats. Prenatal hypoxia led to the suppression of antioxidant defense in the lungs of newborn rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 531–533, May, 1994     

Selection of anxious mice by a three-stage test in an elevated T-maze

Daily testing of SHR and C57Bl/6 mice during 3 days shows an increase of the number of mice with a high level of anxiety, which was determined according to the ratio of the number of entries into the light arms to the total sum of entries into the light and dark arms of an elevated T-maze. Such results were obtained after 3 testings every 3 days in C57Bl/6 but not in SHR mice. This procedure is proposed for the selection of anxious individuals as objects for an anxiety model. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 355–356, March, 1996 Presented by S. N. Golikov, Member of the Russian Academy of Medical Sciences     

Induced activation of peripheral blood mononuclears and neutrophils in recipients of an allogeneic kidney

Peripheral blood mononuclears and neutrophils in recipients of an allogeneic kidney are better stimulated with zymosan and phorbol ester during the first days after transplantation and during allograft rejection. Antithymocytic globulin depresses chemiluminescence of both neutrophils and mononuclears. Antisera to human immunoglobulin suppress chemiluminescence of mononuclears but not of neutrophils. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 523–525, May 1995     

Effect of aminooxyacetic acid on the antidote activity of diazepam under the action of GABA-lytics

Pretreatment of mice with aminooxyacetic acid enhances the antidote activity of diazepam against picrotoxin but not bicuculline. It is claimed that GABA-transaminase inhibitors may be promising candidates as an antidote in complex therapy of seizures induced by GABA-lytics blocking the chloride ionophore. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 4, pp. 441–443, April, 1994     

Adaptation to periodic hypoxia and a diet supplemented with polyunsaturated class ω-3 fatty acids enhance the resistance of Ca2+ transport in the myocardial sarcoplasmic reticulum to free-radical oxidation

The relationship between the level of accumulation of lipid peroxidation products and the status of the Ca²⁺-transporting system in the sarcoplasmic reticulum of the rat myocardium is studied against the background of two cardioprotective factors, namely adaptation to periodic hypoxia and a diet enriched in polyunsaturated fatty acids of the ω-3 class. It is shown that the diet leads to an increase of level of lipid peroxidation products by 1.8 times in the heart and by 19 times in the liver, whereas a adaptation has no effect on the level of lipid peroxidation products in either of these organs. At the same time, the combined action of both factors considerably enhances the resistance of the myocardial Ca²⁺-transporting system to free radical-induced oxidation. Inin vitro experiments it is shown that adaptation to periodic hypoxia results in a more than twofold deceleration of Ca²⁺ transport inhibition during the oxidation induction by the Fe²⁺/ascorbate system; the diet causes a 3.5-fold deceleration of such inhibition. The results show that the accumulation of a high level of lipid peroxidation products is not always followed by damage to the Ca²⁺-transporting system in the myocardial sarcoplasmic reticulum. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 42–45, July, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Influence of the localization of erythroid cell death on erythropoiesis kinetics

The fundamental patterns of influence of the localization of erythroid cell death on cell kinetics are defined with the aid of mathematical modeling. It is established that the kinetic picture is mainly dictated by the region where the death is localized. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 359–360, March, 1996     

Chronobiological characteristics of the activity of the cellular genetic apparatus in surviving sections of rat brain

Diurnal variation of the incorporation of labeled precursors of RNA and proteins into spinal, stem, and cortical populations from the nervous system of rats is studied on surviving sections of the brain. It is shown that in the absence of an effect of other parts of the nervous system, afferentation, and humoral factors isolated nerve cell populations preserve the diurnal rhythm of activity of the genetic apparatus that correlates with the motor activity and the light reception (light-dark cycle) of animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 645–647, June, 1994     

Pathomorphology of radiation-induced changes in bronchi in the long term after exposure

Bronchial biopsies were studied in inhabitants from 3 ecologically contrasting regions in the long term after exposure to radiation. It is established that in bronchial biopsies diffuse atrophy of the mucous membrane is prevalent in the bronchial part of the lungs in an ecologically unfavorable region. Under these conditions a marked decrease of metabolic and proliferative reactions is shown in cell populations of the bronchial wall, as is evident from the data of radioautographyin vitro and stereological analysis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 91–95, January, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Evaluation of the antipyretic effect of psychotropic agents and their influence on the fever-lowering effect of acupuncture

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 115, N ⁰ 3, pp. 262–264, March, 1993     

Ultrastructural analysis of endotoxin-induced transepithelial pinocytosis in the distal part of the nephron

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 115, N ^o 3, pp. 309–312, March, 1993     

Role of mast cells in reparative processes in inflammation

Using the model of acute infectious peritonitis in rats, it is shown that inflammation induced in the absence of mast cells is characterized by marked inhibition of reparative processes. The most significant accumulation of functionally active fibroblasts and the development of granulations and young connective tissue in the mesentery occur 5–10 days after flogogen injection in the natural development of inflammation and after 10–20 days in the absence of mast cells. The data suggest that under natural conditions mast cells directly or indirectly stimulate reparative processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 262–265, March, 1995 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Ion transport and its adrenergic regulation in erythrocyte membranes of the breamabramis brama injected with a mixture of polychlorinated biphenyls

In the first 10 days after the injection of Sovol-54 (a mixture of chlorinated biphenyls) into the breamAbramis brama, considerable alterations in the hormonal regulation of cotranport were observed for erythrocytes of this fish, along with an increase in the passive permeability of their membranes. No significant changes were recorded in Na⁺, K⁺-ATPase activity or its adrenergic regulation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 379–381, October, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences