Evaluation of microsomal and mitochondrial oxidation in rat liver in tetracycline-induced hepatosis

A satistically significant decrease in the content of cytochromes P-450 and b₅ and in the activity of aniline hydroxylase and p-nitroanisole demethylase occurs in rat liver microsomes during the development of experimental acute fatty hepatosis develoing within a 24-h period after intraperitoneal administration of 125 mg/kg tetracycline hydrochloride. Under these experimental conditions tetracycline hydrochloride elicits only an insignificant disintegrating effect on oxidative phosphorylation in liver mitochondria. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 612–615, December, 1994     

Time course of changes in macrophagal activity,metabolic activity of the liver,and hydrocortisone level in mouse serum following injections of bacterial immunostimulants

A relationship is revealed between macrophage activation, suppression of cytochrome P-450-dependent liver monoxygenases, and the hydrocortisone level in the sera of mice in response to bacterial lipopolysaccharides and muramyldipeptide. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 177–180, February, 1996 Presented by M. D. Mashkovskii, Member of the Russian Academy of Medical Sciences     

Effects of phospholipid-containing hepatoprotectors on cytochrome P-450-dependent antitoxic function of the liver during experimental toxic hepatitis

Phospholipid-containing hepatoprotectors essentiale and eplir inhibited conversion of cytochrome P-450 into cytochrome P-420 and restored aminopyrine N-demethylase and anilinen-hydroxylase activities of cytochrome P-450 in rats during acute hepatitis induced by CCl₄ and allyl alcohol. The polyphenol phytopreparation legalon did not prevent degradation of cytochrome P-450. Differences in the effects of hepatoprotectors on the impaired antitoxic function of the liver are probably associated with the abilities of essentiale and eplir to provide phospholipids for regeneration of endoplasmic reticulum membranes of hepatocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 4, pp. 392–394, April, 1999     

Possible mechanisms responsible for the effect of dimedrol on nonsynthetic biotransformation of xenobiotics in rat liver

The ability of dimedrol to inhibit o-demethylation of paranitroanisole, which in rat liver is catalyzed by cytochrome P-450, is demonstratedin vivo andin vitro. The affinity of dimedrol for cytochrome P-450 is higher than that of other xenobiotics. It is suggested that the effect of dimedrol on the metabolism of paranitroanisole and some other xenobiotics is realized during formation of the enzyme—substrate complexes between these substances and cytochrome P-450. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 9, pp. 301–304, September, 1997     

Diurnal time course of hexenal narcosis in experimental hepatosis

A statistically significant circadian rhythm of hypnogenic effect of hexenal is revealed in intact Wistar rats, with the maximum recorded in the daytime and the minimum at night, and an amplitude of at least 30% of the mesor. Circadian rhythms of the analgetic action of hexenal and of α-tocopherol concentrations in the blood serum are found to be in reciprocal relationship. Experimental hepatosis induced by intragastric administration of CCl₄ is attended by alteration of the time organization of the antitoxic function of the liver and of the concentrations of iron, α-tocopherol, and lipid peroxidation products in the blood collected from the hepatic and portal veins. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 540–543, May, 1995 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Subcellular organization of alkane oxidation in the yeast Candida maltosa

After spheroplast lysis and differential centrifugation the alkane monooxygenase system consisting of cytochrome P-450 and the NADPH-cytochrome P-450 reductase of alkane-grown Candida maltosa cells is enriched in the microsomal fraction. This membrane fraction is nearly free of intact mitochondria (cytochrome oxidase) and peroxisomes (catalase), but contains considerable amounts of plasma membrane fractures (azide insensitive, vanadate-sensitive Mg²⁺-ATPase) as demonstrated by biochemical an electron microscopic examinations. By means of sucrose density gradient centrifugation it was possible to separate the cytochrome P-450 containing membranes ( = 1,11 g/cm³) from the plasma membranes ( = 1,18 g/cm³). Therefore the cytochrome P-450 alkane monooxygenase system is most likely localized in the endoplasmic reticulum of the yeast cells. For the following enzymatic steps of terminal alkane oxidation to the corresponding fatty acid a quite different subcellular distribution was observed. The fatty alcohol oxidase and aldehyde dehydrogenase activities are mainly localized in the mitochondrial peroxisomal membrane fraction. During the oxidation of n-alkanes by yeast cells the fatty alcohol should be regarded as an intracellular transport from between the cytochrome P-450 containing endoplasmic reticulum and the sites of its further oxidation in peroxisomes and mitochondria.     

Changes of the level of cytochrome P-450 and NADPH-cytochrome P-450 reductase in rats with hereditary degeneration of the retina

In animals with hereditary degeneration of the retina the level of cytochrome P-450 in the brain microsomal fraction is found to be higher than that in healthy animals. In rats with hereditary degeneration of the retina the activity of NADPH-cytochrome P-450 reductase is unchanged in all tissues examined except for the retina, where it is markedly higher than in healthy animals on postnatal day 90. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 3, pp. 259–261, March, 1994     

Differential induction of natural suppressor activity of bone marrow cellsin vitro by different types of tumors

The suppressor activity of bone marrow cells not adhering to plastic is shown to appreciably increase after their 48-hour joint preincubation with mastocytoma P-815 supernatant or WEHI-3 myelomonocytic strain and to be unchanged after incubation with dupernatants of K-2 erythroleukemic strain or Ehrlich's ascitic carcinoma. P-815, WEHI-3, and K-2 tumors are shown to produce factors characterized by colony-stimulating activity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 184–187, August, 1995 Presented by N. V. Vasil'ev, Member of the Russian Academy of Medical Sciences     

Activity and inducibility of cytochrome P-450-1A in the liver of mice with different sensitivity to hepatocarcinogenic effect of o-aminoazotoluene

Specific activity of cytochrome P-450-1a is detected in the liver of 7 inbred mouse strains sensitive (SWR, C3HA, DD, and CBA) and resistant (AKR, CC57BR, and C57BL) to o-aminoazotoluene-induced hepatocarcinogenesis: 7-ethoxyresorufin-O-diethylase and 7-methoxyresorufin-O-dimethylase, induced by benzo(a)pyrene and o-aminoazotoluene. Mice sensitive (CC57BR and C57BL) and resistant (AKR) to P-450-1a induction were resistant to induction of liver tumor and, similarly, mice both resistant (SWR and DD) and sensitive (C3HA and CBA) to P-450-1a induction were sensitive to hepatic tumor induction. Therefore, there was no correlation between inducibility of cytochrome P-450-1a and sensitivity to o-aminoazotoluene-induced hepatocarcinogenesis at the initial stages of chemical carcinogenesis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 201–203, August, 1998     

Salivary level of volatile fatty acids as an index of the status of the human oropharynx-normal microflora system

Gas-liquid chromatographic determination of the levels and profiles of volatile fatty acids (acetic, propionic, and butyric acids) in saliva samples from healthy volunteers and patients with acute or chronic tonsillitis revealed lowered concentrations of these acids in the saliva of patients and the presence of disease-specific fatty acid profiles. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5 pp. 494–496, May, 1995 Presented by I. V. Domaradskii, Member of the Russian Academy of Medical Sciences     

Reactivity of capillaries and pyramidal neurons in rat cortex under conditions of acutely reduced circulation

A study of capillaries and pyramidal neurons of the cortex in white rats subjected to ligation of the common carotid artery reveals that acute reduction of the circulation is characterized by a decreased activity of alkaline phosphatase and Na, K-ATPase as well as a reduced number of capillaries marked with these enzymes, and a lower activity of butyrylcholine esterase. A decreased activity of cytochrome oxidase in neurons suggests the existence of intracellular compensatory-adaptive mechanisms. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 558–560, May, 1994 Presented by O. S. Adrianov, Member of the Russian Academy of Medical Sciences     

DNA-Bound lipids of thermoresistant and thermolabileShigella sonnei strains

Thin-layer chromatography of DNA-bound lipids of thermolabile and thermoresistantShigella sonnei strains shows a lower content of neutral lipids and higher contents of polyglycerophosphatides and cholesterol in thermoresistant strains. This is regarded as a factor providing for the active state of DNA. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 332–333, September, 1995     

Effects of adaptation to periodic hypoxia on kinetic parameters of respiratory chain enzymes in rat brain

A study of kinetic parameters of brain respiratory enzymes revealed that the maximal velocity and the Michaelis apparent constant for NADH-cytochrome C-reductase are significantly lower in low-resistant rats than in rats with a high resistance to hypoxia. Adaptation to periodic hypoxia increases total resistance only in low-resistant rats. It is accompanied by an increase in the values of kinetics parameters for NADH-cytochrome C-reductase and cytochrome oxidase. Kinetic parameters for these enzymes in the brain of high-resistant rats are either unaltered or even decreased. It is suggested that the first enzymatic complex of the respiratory chain is one of the limiting or regulating links in energy metabolism determining the brain's resistance to hypoxia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 252–255, March, 1996.     

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     

Correction of biotransformation of xenobiotics by α-tocopherol in combination with nicotinamide and methionine in the liver damaged by ultrasound

Six day after rat liver sonication, the content of cytochrome P-450, rate of NADPH oxidation, activity of NADPH—cytochrome P-450 reductase, and rate of aniline hydroxylation in the microsomal fraction decrease. After 12 days, the rate of ethylmorphine N-demethylation also decreases. Intragastral administration of methionine, nicotinamide, and vitamin E for 6 and 12 days activates these enzymes and uridine 5′-diphosphate glucuronyl transferase. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 420–423, April, 1997     

Chemiluminescence study of the contents of the products of Cu2+-induced lipid peroxidation in different fractions of human blood lipoproteins

It is demonstrated that the content of the primary products of lipid peroxidation reaches the maximum after about 1-h incubation with Cu²⁺ and then declines. At a Cu²⁺ concentration of about 10–15 μM, the content of lipid peroxidation products is maximal; it does not rise with a further increase in the Cu²⁺ concentration. Comparison of the kinetics of lipid peroxidation in different lipoprotein fractions shows that low density lipoproteins are much more strongly oxidized than high density lipoproteins. A strong positive correlation between the amplitude of the chemiluminescence burst and the diene conjugate content is established in 79 independent measurements. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2, pp. 144–148, February, 1995     

Effects of adaptation to hypoxia on cytochrome levels in the brain and liver of rats

After a prolonged (for 30 days) adaptation of rats to intermittent hypoxia, their brains contained lowered levels of mitochondrial cytochromes, despite an increase in the number of mitochondria in the brain tissue mass, along with similar levels of high-energy compounds and more protein as compaired to the brains of unadapted controls. A mitochondrial population with novel properties presumably emerged in the brain. These effects were all more strongly marked in rats with an initially low resistance to hypoxia. In the liver of hypoxiaadapted animals, unlike in their brain, cytochrome levels in the mitochondrial and microsomal redox chains were lowered and the biogenesis of mitochondria was much less intensive. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 576–579, December, 1995     

Protective effect of carnosine in hyperthermia

Under the conditions of hyperthermia, carnosine (β-alanine-l-histidine) normalizes tissue contents of lipid peroxidation products, cytochrome P-450, serotonin, and histamine in rats and increases their survival after extreme hyperthermia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 50–52, July, 1997     

Content of 2,3-diphosphoglycerate and adenosine triphosphate in erythrocytes and the acid-base balance in adult and newborn rats during acute hypoxia

It is shown that in deep acute hypoxic hypoxia the 2,3-diphosphoglycerate content is reduced and the adenosine triphosphate content unchanged in the erythrocytes of newborn rats. Under the same conditions adult animals show an increase of 2,3-diphosphoglycerate and a drop in the adenosine triphosphate content in the erythrocytes. The importance of these changes is discussed in terms of the mechanisms regulating the oxygen-transporting function of erythrocytes during acute hypoxic hypoxia in newborn and adult animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 631–633, June, 1995 Presented by M. Ya. Studenikin, Member of the Russian Academy of Medical Sciences     

Effect of cytochrome C and its derivatives on the circulation and oxidative metabolism of the ischemized brain

The effects of animal and biotechnological cytochrome C and its hemtetradecapeptide in a heme-isomolar dose on the cerebral bloodflow, oxygen and glucose consumption, and pH of the ischemized brain were studied in cat experiments. Cytochrome of both types and hemtetradecapeptide increased the consumption of oxygen and glucose by ischemized brain tissue and somewhat reduced the development of acidosis. The shifts of oxidative metabolism parameters of the ischemized brain correlated with inhibition of the development of postischemic hypoperfusion of the brain. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 640–642, December, 1995 Presented by P. V. Sergeev, Member of the Russian Academy of Medical Sciences