Investigation of the mechanism of action of ouabain and cyclic AMP of the transport of calcium ions by rat heart mitochondria

The action of ouabain and cyclic AMP on the Ca-accumulating capacity and outflow of Ca²⁺ ions from loaded rat heart mitochondria was studied by the tetracycline probe method. In the course of the investigations no effect of ouabain on these processes was found. Cyclic AMP did not act on Ca binding by the mitochondrial membrane but it induced rapid liberation of Ca²⁺ from organelles loaded with these ions.Department of Molecular Pharmacology, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S. debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 158–160, February, 1977.     

Effects of apolipoproteins C on oxidative phosphorylation in rat liver mitochondria

It is shown that apoC-III, but not other apoC proteins, components of very low density lipoproteins (apoC-I, apoC-II, apoC-III), reduced the rate of mitochondrial respiration in various metabolic states. This effect depended on the dose of apoprotein, type of oxidized substrate, and the presence of Ca ions in the incubation medium. ApoC-III completely blocked oxidative phosphorylation during oxidation of palmitoyl carnitine by mitochondria, while the respiration rate in metabolic state 4 remained unchanged. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 184–186, August, 2000     

Effect of doxorubicin on oxidative phosphorylation in brain mitochondria

Inin vitro experiments, antineoplastic anthracycline antibiotic doxorubicine caused deenergization of rat brain mitochondria due to oxidation-phosphorylation uncoupling and inhibition of succinate oxidase system. Reduced production and oxidation of succinic acid is the most early effect of doxorubicin on mitochondrial oxidation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 10, pp. 445–447, October, 1999     

Intravital distribution of chelating agents in the tissues

Injection of dithisone and quinoline compounds into animals leads to the intravital formation of granules of a zinc chelate in the tissues that can be detected in frozen sections. The intensity of the intravital histochemical reaction depends on the complex-forming capacity, dose, and mode of administration of the agent and also on the presence of other ligands reducing its use in the coordination of volume.Department of Pathological Anatomy and Central Research Laboratory, Tomsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR I. V. Toroptsev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 3, pp. 292–293, March, 1977.     

Mechanisms of reciprocal control of reactions and processes involved in energy production by mitochondria

Correlations between respiration rates in the mitochondria in different states are studied using various oxidation substrates. Specific features and integration between different functional cycles are substrate-dependent. It is suggested that variations of the mitochondrial function correspond to specific phases of pathological process. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 9, pp. 282–284, September, 1996     

Two-factor correlation analysis of the distribution of morphofunctional properties of mitochondria during irradiation

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol.115, N ^o 2, pp.215–218, February, 1993     

The correction of postvagotomy disturbances of small intestine motility with antihypoxants and antioxidants

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N ^o 8, pp. 132–134, August, 1993     

Phospholipid composition of liver mitochondria in experimental hemorrhagic shock

Heparin used as an anticoagulant in modeled hemorrhagic shock decreases the phosphatidylcholine and increases the phosphatidylethanolamine contents in the mitochondria. Accumulation of lysophosphatidylcholine in whole mitochondria and their inner membrane is observed in hemorrhagic shock. At the same time, hemorrhagic shock decreases phosphatidylcholine content in the inner and outer mitochondrial membranes and increases phosphatidylethanolamine content in the outer membranes. Modification of phospholipid composition of mitochondrial membranes is a mechanism responsible for impaired energy production in liver mitochondria in hemorrhagic shock. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 43–45, July, 1997     

Effect of intraperitoneal spermin on oxidative processes in isolated mitochondria of rat liver in hypothermia

Effect of intraperitoneal administration of spermin on oxidative phosphorylation and calcium capacity of isolated liver mitochondria was studied in normo- and hypothermic rats. Hypothermia stimulates mitochondrial respiration without decreasing the contingency and increases calcium capacity. Spermin suppresses mitochondrial respiration, the effect being stronger in hypothermia. In high doses spermin prevents stimulating effect of hypothermia on respiration and reduces the increase in calcium capacity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 5, pp. 526–528, May, 1998     

Changes in the state of mitochondria and intercellular junctions of hepatocytes for the internal application of siliceous water

Structural-adaptive alterations in mitochondria and intercellular junctions are found in the liver against the background of elevated silicon when mineral siliceous water and silicon solution are applied internally. It is established that an increase of the number of tight and gap junctions takes place during the period of declining bioenergetic processes in hepatocytes. As the number and area of mitochondria increase, the extent of the intercellular junctions shrinks. These changes may be considered to be important components in the mechanism of action of siliceous water. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 348–351, March, 1996 Presented by V. V. Kupriyanov, Member of the Russian Academy of Medical Sciences     

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     

Effect of antioxidants,antihypoxants, and actoprotectors on the binding ability of serum albumin during intoxication with tetrachloromethane

A decline in serum albumin content and a tendency toward a decrease in the binding constant of the negatively charged fluorescent probe 1-anilinonaphthalene-8-sulfonate are observed in acute intoxication with tetrachloromethane. The mean number of binding sites per albumin molecule increases, therefore, the total concentration of the binding sites for serum albumins remains practically unchanged. Pretreatment with antioxidant, antihypoxant, or actoprotector increases serum albumin content (tomerzole) and partially normalizes its conjugational parameters: binding constant (sodium γ-oxybutyrate) and mean number of binding sites per molecule (dibunol, tomerzole). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 12, pp. 635–637, December, 1996     

Effects of some steroid hormones on Ca2+ transport and oxidative metabolism of isolated mitochondria

Effects of prednisolone, estradiol, and testosterone on the transport of Ca²⁺ and the respiration induced by it in the heart and liver mitochondria of rats were studied. Prednisolone and testosterone were found to reduce the Ca-accumulating capacity of the mitochondria, the rates of ion entry and exit, and the rate of Ca²⁺-induced respiration. Estradiol, while inhibiting Ca²⁺ transport across mitochondrial membrane, did not influence the respiration in the phase of Ca²⁺ absorption, but accelerated it in the phase of ion exit. These data suggest that due to their lipophilic properties, the steroids become incorporated in the mitochondrial membrane, thereby changing its viscosity and permeability and limiting the mobility of transmitter proteins. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 616–618, December, 1994     

Altered activity of respiratory chain enzymes in mitochondria of peripheral blood lymphocytes after irradiation in rats

The effect of ionizing radiation on the activity of succinate dehydrogenase (complex II) and succinate-cytochrome C-oxidoreductase in peripheral blood lymphocytes is studied on rats exposed to whole-body γ-irradiation in doses of 9.5–10.5 Gy. On day 5 after irradiation, when the number of lymphocytes is sharply reduced, enzyme activity in the remaining population is found to be reliably increased. These changes are not related to biological cycles. It is assumed that most of the survivors after high-dose irradiation are the cell populations maintaining a high level of oxidative phosphorylation in mitochondria. Translated fromByulleten' Eksperimental'noi Giologii i Meditsiny, Vol. 120, N ^o . 8, pp. 158–159, August, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Electron-cytochemical and morphometric investigation of enzyme activity in thyrocyte mitochondria during carcinogenesis

Activity of cytochrome oxidase and succinate dehydrogenase in the mitochondria of thyroid gland cells of rats was studied by electron-histochemical and morphometric methods during experimental carcinogenesis. The activity of these enzymes in the mitochondria was shown to vary depending on the stage of malignant transformation: In the early stages it was close to normal, but later (precancer) it fell sharply and approached the level observed in the mitochondria of cancer cells. A marked decrease in the activity of the enzymes studied in the morphologically altered mitochondria of cancer cells may be a qualitative characteristic of these cells.Electron Microscopy Room, N. K. Kol'tsov Institute of Developmental Biology, Academy of Sciences of the USSR. Laboratory of Electron Microscopy, Institute of Poliomyelitis and Virus Encephalitis, 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. 4, pp. 452–455, April, 1977.     

Changes in phospholipid composition of mitochondria in the medulla oblongata and frontal lobes of the cerebral hemispheres in hemorrhagic shock in cats

Considerable regional differences in the phospholipid composition of mitochondrial membranes are found in the brain of cats in the terminal phase of hemorrhagic shock. The most prominent alteration is noted in the medulla oblongata and consists in a progressive elimination of phosphatidylcholine. Changes in the main phospholipids in mitochondrial membranes of the cerebral hemispheres are less pronounced and consist in a drop of phosphatidylinositol and phosphatidylethanolamine. Accumulation of lysophosphatidylcholine and lysophosphatidylethanolamine is a regular feature of the studied mitochondria. Accumulation of lysophosphatidylserine is found primarily in mitochondrial membranes of the medulla oblongata. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 4, pp. 387–391, April, 1996     

Physicochemical properties of membranes and functional status of liver mitochondria in rats with an inherited capacity for increased radical formation

Liver mitochondria of inbred W/SSM rats with inherited increased radical formation reveal the following anomalies: inhibition of oxidative phosphorylation, a lowered transmembrane potential, and alterations in protein-lipid interaction. The membrane viscosity and osmotic stability of mitochondria are unaffected. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 628–631, June, 1995     

Effects of adaptation to intermittent hypoxia on oxidative phosphorylation in brain mitochondria of rats with different sensitivities toward oxygen deficiency

After long-term adaptation to intermittent hypoxia, rats with an initially low resistance to acute oxygen deficiency were 2 to 4 times more resistant to it, while highly resistant rats did not show a significant change in resistance. The adaptation was accompanied by weakening of the electron-transporting function of the respiratory chain and increasing efficiency of oxidative phosphorylation in the brain mitochondria oxidizing NAD-dependent substrates, indicating that energy was produced in a more economical way. The succinate oxidase pathway of oxidation was found to be utilized to only a limited extent as a compensatory mechanism in animals exposed to intermittent hypoxia over a prolonged period. The effects of adaptation were more marked in the brain mitochondria of rats initially highly sensitive to oxygen deficiency. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 572–575, December, 1995     

Effect of repeated cold stress on intensity of lipid peroxidation and tissue antioxidant system

Repeated cold stress performed in a cold-tempering mode reduces lipid peroxidation and activates tissue antioxidant system. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 4, pp. 385–387, April, 1998