The target cell plasma membrane and steroid hormones: the beginning or end of the debate?

Drawing on experience gained in previous studies, the authors propose their own approach to defining the role the plasma membrane of the target cell plays in the mechanism of action of steroid hormones. The properties of membrane receptors for glucocorticoids on lymphoid cells are identified and examined, and possible ways in which the hormonal signal is transformed into a biological response of the target cell are described. The results provide a theoretical basis for the development of novel diagnostic techniques and pharmaceutical preparations. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 342–348, October, 1995     

Effect of exogenous acetylcholine on neuromuscular transmission in the stimulated rat diaphragm

Nerve stimulation is performed in rat phrenicodiaphragmal preparations with armine-inhibited acetylcholinesterase. Acetylcholine (1×10⁻⁷ M) is added to the saline for 15 min, and as it is washed off (during 1–2 h), the amplitude of isometric contractions and of the total action potential increases in the continuously stimulated muscle. Contractions in response to direct muscle stimulation remain unchanged. The membrane resting potential of muscle fibers exposed to acetylcholine shifts by 2–3 mV toward hyperpolarization and remains at this level for 2 h after the removal of acetylcholine from the saline. Presented by S. N. Golikov, Member of the Russian Academy of Medical Sciences Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 457–459, November, 1994     

The invertor mechanism of changes in the plasma membranes of hepatocytes during induction of microsomal monooxygenases in adult and old rats

Age-specific changes of some parameters of the state of the plasma membrane are studied for genetic induction of enzymes of microsomal oxidation. Changes of the state of plasma membrane of hepatocytes are shown to be associated with the synthesis of a specific intracellular regulator (invertor). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 13–15, January, 1994     

Stimulation of proliferative activity of human natural killers (CD16+CD56+ cells) by recombinant interleukin-3in vitro

The proliferative activity of human natural killers (CD16⁺CD56⁺ cells) in the presence of 100 and 1000 IU/ml human recombinant interleukin-3 is investigatedin vitro. It is shown that recombinant interleukin-3 reliably enhances natural killer proliferation, causing a 9–15.2-fold increase of³H-thymidine uptake by CD16⁺CD56⁺ cells both in complete culture medium and in conditioned medium. The effect of the factor is 3.9–6.4 and 3.6–8.9-fold more potent than that of recombinant interleukin-2 and granulocyte-macrophage colony-stimulating factor, respectively, in the same doses. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 409–412, April, 1995 Presented by S. V. Prozorovskii, Member of the Russian Academy of Medical Sciences     

Comparative study of the effects of recombinant tumor necrosis factor and synthetic peptides corresponding to its fragments on phagocytosis mediated by Fc- and MF-receptors

The effects of human recombinant tumor necrosis factor and its peptides on the macrophage-like cells of continuous cell line P388D1 were studied. One of the peptides, 123–131, was found capable of not only mimicking, but also of blocking the effects of recombinant tumor necrosis factor. The results permit us to tentatively identify the 123–131 site of the factor molecule as being responsible for its activating effect on macrophages. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 304–308, March, 1996 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

The efficacy of bronchodilators is determined by electrostatic interactions

Donnan potential recordings demonstrate that the preparation troventol exhibits a positive surface charge, atropine sulfate a negative surface charge, and atrovent a charge close to zero. Analysis of electrostatic interactions between these preparations and cells reveals that alveolar macrophages exhibit a more negative surface charge than peritoneal macrophages. More pronounced electrostatic interactions of the preparations with membrane macrophages are observed with troventol versus the other broncholytics studied. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 476–478, November, 1994     

Toxic effect of glutamate causes mitochondria damage in granule cells of dissociated cultures of rat cerebellum

It is shown that treating rat cerebellum with glutamate in a neurocytotoxic concentration causes a drop of the mitochondrial membrane potential in granule cells and leads to ultrastructural alterations of mitochondria in these neurons. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 378–380, April, 1995. Presented by the late Member of the Russian Academy of Medical Sciences     

Morphogenesis of a canalicular-hypertensive model of pancreatitis

A rat model of acute pancreatitis is presented. Its conformity to the pancreatic changes during human pancreatitis is shown. The morphology of experimental pancreatitis development in rats is studied. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 89–91, January, 1995     

Inhibition of mitogen-stimulated proliferation of human lymphocytesin vitro by synthetic peptide fragments of α-2 interferon

Human α-2 interferon and peptides representing parts of the amino-acid sequence 124–138 of the IF molecule inhibit the proliferative response of peripheral blood lymphocytes from healthy donorsin vitro induced by ConA. It is shown that neither interferon α-2 nor biologically active peptides change the level of interleukin-2 ConA-induced production by human blood mononuclears. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 72–74, January, 1994 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Effect of monochromatic red and near-infrared light on the adhesive properties of the cell membrane: Dependence on wavelength

Changes in the adhesive properties of the cell membrane after irradiation of HeLa cells with monochromatic visible and near-infrared radiation (λ=580–860 nm, i=1.3 W/m², t=40 sec, D=52 J/m²) are assessed as the number of adherent cells. Three spectral regions (600–625 nm, 645–700 nm, and 720–860 nm) with the maximums near wave-lengths 620, 680, 750, and 825 nm are identified, where the adhesive properties of the cell membrane are observed to be enhanced. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 670–672, June, 1994 Presented by V. P. Solov'ev, Member of the Russian Academy of Medical Sciences     

Ambiguity of the effect of high and low doses of amino-acid preparations on the immune response and phagocytosis in mice

It is shown that the effect of amino-acid preparations (levamine-70–70, cerebrolysin, and aviamine) is dose-dependent. Thus, levamine-70 and cerebrolysin at 65 mg/kg do not affect the immune response but stimulate phagocytosis. Aviamine at 65 mg/kg inhibits the immune response but stimulates phagocytosis and in a dose of 6.5×10⁻² mg/kg boosts both processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 500–501, May, 1994 Presented by A. D. Ado, Member of the Russian Academy of Medical Sciences     

Effect of dimethylsulfate on the structure and cytoarchitectonics of rat thymus

Changes of structure and cell ratios of different functional zones in the thymus under conditions of long-term dimethylsulfate administration at 0.1 and 2.0 mg/m³ on the organism are studied morphometrically on histological preparations from Wistar rats. Cyclic reactions of the thymus to the toxic substance are found to be due to compensatory processes. It is shown that the nature of the reaction does not depend on the concentration of toxic substance but that the extent of changes is a function of the dimethylsulfate concentration. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 96–100, January, 1995     

Ultrastructure of erythrocytes during calcium-inducedin vitro aging

Vesiculation of the plasmalemma followed by fragmentation to microvesicles and formation of microspherocytes are shown to be the main phenomena during aging in rat erythrocytes. In human erythrocytes microvesiculation from the apexes of echinocyte spicules and hemolysis in echinocytes II–IV are predominant. Hemolysis, vesiculation, and microvesiculation are observed in rabbit, and hemolysis and microvesiculation in canine erythrocytes. An increased level of free fatty acids (about 30% per hour) in human and rat erythrocytes is also detected. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 555–558, May, 1994 Presented by N. K. Permyakov, Member of the Russian Academy of Medical Sciences     

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     

Identification of specific binding sites for nerve growth factor on human blood platelets and membranes from bovine brain

The presence of specific binding sites for nerve growth factor on membranes from bovine brain and human blood platelets is shown. The association and dissociation kinetics and the dissociation constants of receptor binding of nerve growth factor are analyzed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 295–297, March, 1996 Presented by N. P. Bochkov, Member of the Russian Academy of Medical Sciences     

Role of glycolysis in the maintenance of the energy-synthesizing function of hepatocytes from rats adapted and nonadapted to hypoxia at different oxygen concentrations

It is demonstrated that the lactate-Po₂ dependence is the same in hepatocytes of rats with high and low resistance to hypoxia and does not correlate with phasic changes in the ATP concentration in the 890–50 μM O₂ region. Strong activation of lactate formation against the background of ATP decrease indicates that glycolysis is not the major mechanism determining the steady-state ATP level in the cell and affecting the ATP-Po₂ relationship in a wide range of oxygen concentrations. The intensity of glycolysis in hepatocytes of rats with high resistance to hypoxia is markedly increased after periodic adaptation to hypoxia but remains practically unchanged in the hepatocytes of low-resistance rats. This indicates that fundamentally different compensatory mechanisms are involved in this process in the liver of high- and low-resistance rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 28–32, January, 1995     

Immunochemical analysis of common antigenic determinants in insulin and apoprotein B Molecules

A study is performed of the mechanism underlying stress diabetes, which develops in human beings and animals under stress. Dot-immunoanalysis shows the presence of common antigenic determinants in insulin, apoprotein B, and apoprotein B-containing low density and very low density lipoproteins isolated from human and rat serum. Electrophoresis, immunoelectroblotting, and immunoenzyme analysis reveal 5–6 peptides belonging to apoB, which specifically react with anti-insulin and anti-very low density lipoprotein antibodies. Insulinlike immunoreactivity is also identified in human serum supernatant obtained after precipitation of the total low density and very low density lipoprotein fraction and after removal all lipoproteins from it. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 258–261, September, 1994     

Immunocytochemical study of the localization of scavenger receptor in human aortic smooth-muscle cells

Scavenger receptor was soughtin situ in human aortic smooth-muscle cells and in a primary culture of intact human aortic intima using antibodies to scavenger receptor. For identification of smooth-muscle cells, double staining making use of antibodies to murine α-actin was used. The presence of scavenger receptor in smooth-muscle cells of the intima and media of human aorta was demonstrated on aortic slices. In cultured smooth-muscle cells from normal human aortic intima scavenger receptor was distributed over the entire surface of the cell membrane, forming clusters in some places. These results suggest that human aortic smooth-muscle cells express scavenger receptor. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 195–198, August, 1995 Presented by V. N. Smirnov, Member of the Russian Academy of Medical Sciences     

Mechanisms of the vasodilator effect of nitroglycerin and chlorpromazine and specificities of their interaction in a model of isolated rat thoracic aorta

The effect of nitroglycerin and chloropromazine (plegomazin) on norepinephrine-induced contraction of rat aorta rings is studied in experiments on the intact and deendothelized aorta, and the combined myolytic effect of the two preparations is assessed. A possible cross-tolerance between nitroglycerin and chloropromazine is studied in experiments simulating the development of vascular tolerance of nitroglycerin. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 273–276, September, 1994 Presented by P. V. Sergeev, Member of the Russian Academy of Medical Sciences     

Polyunsaturated phosphatidylcholine micelle-induced decrease of atherogenicity of the serumin vitro

It is shown that polyunsaturated phosphatidylcholine administered in micelles stabilized by a plant-derived glycoside prevents the accumulation of cholesterol by cells incubated in atherogenic serum and, moreover, in certain cases causes a 1.4–1.5-fold drop of intracellular cholesterol as compared to control cells. The optimum antiatherogenic effect was achieved when using a micelle concentration of 100–200 μg/ml and an incubation time of at least 4 hours. The antiatherogenic effect was analogous to the effect of high density serum lipoproteins. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5 pp. 497–501, May, 1995 Presented by Yu. M. Lopukhin, Member of the Russian Academy of Medical Sciences