341. [The activation of the transposition cycle Ty element by the reverse transcriptase of the human immunodeficiency virus in Saccharomyces cerevisiae yeasts].342. [The hormonal regulation of mRNA Na,K-ATPase expression in rat kidneys in postnatal ontogeny].
作者: N S Logvinenko.;T M Khlebodarova.;E I Solenov.;L N Ivanova.;N E Broude.;G S Monastyrskaia.
来源: Tsitologiia. 1991年33卷11期18-25页
A study was made of effects of aldosterone, aldosterone+dexamethasone, and aldosterone+spironolactone on Na,K-ATPase mRNA expression in renal cortex of adult and 10 day old rats, when kidney is not sensitive to the hormone injection. It is shown that hormonal induction of synthesis of Na,K-pump mRNA occurs in the early postnatal period apart from mineral corticoid receptors. It seems probable that aldosterone exerts its action in 10 day old rats by interaction with glucocorticoid receptors inducing synthesis of different amounts of alpha- and beta-subunits of Na,K-ATPase.
343. [Regulation of beta-galactosidase synthesis in Escherichia coli by exogenous cyclic 3',5'-adenosine monophosphate].
The effect of cyclic 3',5'-adenosine monophosphate (cAMP) on the rate of beta-galactosidase biosynthesis was studied in the cells of Escherichia coli M-17 growing in MPB and mineral media with glucose and maltose, i.e. under the conditions of various catabolite repression, as well as upon lac-operon induction by isopropyl-beta-D-galactopyranoside (IPGP). The stimulating action of exogenous cAMP was found only in a medium with salts and glucose. The induction by IPGP was highest during the growth in a medium with glucose and maltose. When the medium contained IPGP, cAMP accelerated the enzyme synthesis in all media, but only at the early growth phases, while cAMP eliminated the effect of IPGP at the stationary phase of growth. The regulation of beta-galactosidase biosynthesis by cAMP demonstrated for the first time that this effect depended on the physiological state of E. coli: the expression of catabolite-sensitive E. coli genes was subject to both positive and negative regulation in one and the same inducible system. The effect exerted by cAMP depended on the nature of a carbon source in the growth medium.
344. [Expression of cloned bialaphos resistance gene (bar) in Streptomyces strains].
The object of the study was a strain of Streptomyces hygroscopicus producing bialaphos, an antibiotic used as a herbicide, which is promising and ecologically safe. Molecular cloning of a bialaphos resistance gene (bar) was performed in the recipient strain, S. lividans TK64, within the 2.0-kb DNA fragment with the plasmid pIJ699. Introduction of a bar gene into another strain producing bialaphos, i.e. S. viridochromogenus Tu494, led to its higher constitutive resistance to bialaphos. The results confirmed the data on different regulation of bar (S. hygroscopicus) and pat (S. virido-chromogenus) resistance genes.
345. [The interferon system: inhibitors of interferon action].
The review of the literature data and the authors' data on interferon action inhibitors being one of the components of interferon system is presented. The methods of the production of various types of interferon action inhibitors, their characteristics and the main differences between them are described. The possible mechanisms of inhibitors' actions are considered. It was shown that the study of interferon action inhibitors is important in both the theoretical and practical aspects.
346. [Fundamentals of antimicrobial chemotherapy: new data].347. [The regulation of the ontogenetic expression of the heat-shock genes from puff 67B in the salivary glands of Drosophila melanogaster].
The 67B locus contains a cluster of heat-shock genes, four of which (hsp22, hsp23, hsp26, hsp28) are ecdysterone-inducible. Experiments on the transcription of these genes in salivary glands of pupating larvae showed that hsp23 and hsp28 mRNAs were most abundant in the larvae while hsp26 and hsp22 had intermediate or low level of accumulation, respectively. The second series of experiments have demonstrated that mutations of ecs gene or its deletion reduce either the transcription rate or stability of small hsp mRNAs. The resulting level of hsp23 and hsp28 mRNA accumulation was 70% and 40%, respectively, for the t143 mutant and 20% for the t10 mutant, as compared with the control. Mutations t435 and t324, as well as complete deletion of the ecs gene produced a greater damaging effect: the abundance of hsp23 mRNAs in the salivary glands of the appropriate larvae was reduced no less than by a factor of 10, 40 and 75, respectively. Our data show that ecs gene performs its regulatory function at the transcriptional level.
348. [The effect of a fluorocarbon emulsion--an enzyme inducer of the cytochrome P-450-dependent monooxygenase system of the liver--on the acute toxicity of CCl4 and on the efficacy of the prophylactic use of antidotes in organophosphate pesticide poisoning].
作者: G M Mikhaĭlov.;A A Varykhanov.;L A Omarova.;V E Verovskiĭ.;V V Obraztsov.
来源: Farmakol Toksikol. 1990年53卷4期60-2页
The effect of intraperitoneal administration of perfluorocarbon emulsion, an inducer of cytochrome P-450-dependent monoxygenase system of the liver, on the resistance of rodents to the action of CCl4 and organophosphorus pesticides was studied. Perfluorocarbon emulsion potentiated CCl4 toxicity decreasing LD50 from 4.5 to 3.7 mg/kg mouse body weight without changing susceptibility of rats to organophosphorus pesticides. A preliminary administration of perfluorocarbon emulsion effectively increased the protective action of antidotes (atropine + dipyroxime) providing the resistance of the animals to 12-fold, 20-fold and 20-fold LD50 of dichlophos, methaphos and butiphos, respectively.
349. [Serum amine oxidase activity and the methods of its correction in patients with arterial occlusive diseases of the extremities].
The article presents results of examination of blood serum ++amine oxidase++ in 78 patients with obliterating diseases of the extremity arteries. It was found that enzyme activity was dependent on the form and stage of the disease. The data obtained were used for the examination and medicamentous correction of the enzyme activity.
350. [The effect of liposomes on the hormonal induction of liver tyrosine aminotransferase in an experiment].
Liposomes prevented the hydrocortisone-produced induction of tyrosine aminotransferase in animal liver tissue under conditions of normal state and of alcohol intoxication. The inhibitory effect of liposomes appears to be mainly based on their ability to incorporate into hepatocyte membranes, due to which the membrane permeability towards hydrocortisone was altered.
351. [Phenomenon of enzymatic imprinting in adult animals].
An inductor of a system of multifunctional monooxygenases, the sovol, being applied to hepatectomized adult rats, produced an enzymatic imprinting, which was expressed in a long-term increase in the aryl hydrocarbon hydroxylase, 7-ethoxycoumarin-deethylase and amidopyrine-N-demethylase activities, as well as in the metabolic activation of benzo (a)-pyrene by the liver S9-fraction in the Salmonella/microsome assay. The phenomena of enzymatic imprinting in adult animals, primarily described, is a reflection of response universality of proliferative cells upon inductors action.
352. [The functional topography of the digestive enzymes in the gastrointestinal tract and in nondigestive organs (liver, kidney) in the ontogeny of rats and the effect of inducing agents].
作者: A A Nikitina.;V V Egorova.;N N Iezuitova.;N M Timofeeva.;A M Ugolev.
来源: Zh Evol Biokhim Fiziol. 1990年26卷2期273-6页
Activities of the digestive enzymes (lactase, maltase, saccharose, di-, tri- and aminopeptidases, alkaline and acid phosphatase) in the gastrointestinal tract, the kidney and the liver in one-day-old and adult rats as well as in 10-day-old rats after injections of hydrocortisone (H) or thyroxine (T4) were determined. On the basis of the results obtained it is summarized that (1) high levels of the digestive enzyme activities are observed in the nondigestive organs in immature and adult rats; (2) H induces the enzyme activities in the small intestine more than in other organs; T4 does not influence the activities of the most of enzymes studied both in the digestive and in the nondigestive organs; (3) high activities of a number of enzymes in the colon in one-day-old rats implies its involvement in the digestion at early stages of the ontogenesis.
353. [Immunomodulators with an 8-azasteroid structure as inducers of liver cytochrome P-450].
作者: B B Kuz'mitskiĭ.;I G Dad'kov.;A E Mashkovich.;O V Stoma.;L M Slepneva.
来源: Farmakol Toksikol. 1990年53卷2期52-5页
Two structural analogues of D-homo-8-azasteroids, both an immunostimulant and an immunodepressant, are inductors of the liver cytochrome P-450 in animals. This capability was shown by means of both a decrease of the hexenal sleep duration in the pharmacological test and an increase of the quantity of cytochrome P-450 and the rate of N-demethylation of aminopyrine in the biochemical assays.
354. [Changes in the content of cytochrome P-450 and the activity of microsomal and cytosolic glutathione transferases in the liver of guinea pigs undergoing cutaneous application of various doses of mineral oil made from petroleum containing polycyclic aromatic hydrocarbons].
Guinea pigs received skin application of petroleum-derived mineral oil distillate, containing about 10% of polycyclic aromatic hydrocarbons with the 4 hours exposure time everyday during 20 days. 100% distillate preparation and it's 50%, 3% or 0.5% solutions in furfurol and ethanol are used. It resulted in the distillate-dose-dependent cytochrome P-450 induction (1.38-2.23-fold) in liver of the all exposed groups of guinea pigs and in 20-60% decrease in microsomal and cytosol glutathione transferase activities in groups which received 50% and 3% mineral oil distillate solutions. Ratio values of cytochrome P-450 content level to glutathiontransferase activity level depended linearly on the distillate doses, and it increased 2.7-4.4-fold with the distillate concentration increasing in the preparation from 0.5% to 50%. Conclusion was made that with increasing distillate doses the process of polycyclic aromatic hydrocarbon activation with the genotoxic metabolite formation predominated over the process of those metabolite detoxication.
355. [Induction of cytochrome P-450 forms by prolonged administration of nifedipine].
作者: L F Guliaeva.;A Iu Grishanova.;V M Mishin.;M Koleva.;Ts Stoĭchev.;V V Liakhovich.
来源: Biull Eksp Biol Med. 1990年109卷2期148-50页
In experiments on male Wistar rats it has been found that nifedipine applied in a dose of 10 mg/kg body weight i.p. daily for 20 days did not significantly increase the total amount of cytochrome P-450 but markedly increased the 7 alpha-, 16 beta- and 6 beta-hydroxylation of androstenedione in liver microsomes, suggesting the induction of cytochromes P-450a, P-450b and P-450p respectively. The induction of cytochrome P-450b was also confirmed immunochemically with polyclonal antibodies against cytochrome P-450b/e.
356. [Ziksorin in the combined treatment of psoriasis].357. [The correction of disorders in the microsomal oxidation system of the liver in experimental acute liver failure].
The effect of inductors and hepatic protectors on the detoxification function of the liver was studied in male rats with acute renal insufficiency (ARI). All the agents which were studied (phenobarbital, silibor, zixorin) caused an increase in the content of cytochromes P450 and b5 and in the activity of the main microsomal enzymes in the liver of rats with ARI. At the same time the survival of animals with ARI increased. The use of inductors and hepatic protectors as measures of pathogenetic therapy in disturbed detoxification function of the liver in ARI is promising.
358. [Cytochrome P-450 induction and the subsequent induction of an immune response in rats during the chronic administration of xenobiotics].
The long-term administration of xenobiotics carcinogens o-aminoazotoluene (o-AAT) and benz(a)pyrene (BP) to rats was found to cause induction of the liver cytochrome P-450 system which gradually decreases in spite of continued administration of the agents. Induction of microsomal oxygenases under these conditions is followed by induction of the immune response to o-AAT and BP. The data obtained correspond to the conception of the immunochemical functional system of homeostasis implying that the cytochrome-450 system and the immunity system are functionally linked and are elements of the common functional adaptive system of the organism.
359. [The effect of inducers of microsomal enzymes on glucose transport in the kidneys].
Phenobarbital (50 mg/kg), benzonal (35 mg/kg) and zixorine (100 mg/kg) administered orally for 4 days and 3-methylcholanthrene (20 mg/kg) administered subcutaneously for 2 days decreased the maximal tubular transport of glucose in rats. Phenobarbital (10 mg/kg) given orally for 8-10 days reduced the tubular reabsorption of glucose in dogs. An increase of phenobarbital dose enhanced and prolonged its effect on the renal tubular transport of glucose.
360. [Effectiveness of a new Soviet drug Benzonal, inductor of microsomal enzymes of the liver, in the complex treatment of hemolytic disease of newborn].
The effects of benzonal on the course of neonatal hemolytic disease due to the Rhesus factor-conflict was studied in comparison with that of phenobarbital. Dynamic follow-up of infants in the early neonatal period showed benzonal to produce a more pronounced hypobilirubinemic effect which was manifested as a prompter disappearance of skin jaundice and lower percentages of complications. By depressing the activity of organospecific enzymes and lowering the serum biliary acid levels, benzonal promotes normalization of the metabolic shifts present in neonatal hemolytic disease. The findings make it possible to recommend the new inductor of microsomal liver enzymes benzonal as part of the combined therapy of neonatal hemolytic disease.
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