[Effect of plague "murine" toxin on activity of antioxidant system in cells of experimental animals].

AIM: To study nature of changes in components of glutathione disulfide system of experimental animals influenced by plague "murine" toxin. MATERIALS AND METHODS: Total glutathione level as well as levels of oxidated (G-SS-G) and reduced (GSH) forms of glutathione, activity of glutathione reductase and glutathione peroxidase in erythrocytes of Mongolian gerbils (Meriones unguiculatus), mice and guinea pigs were studied. RESULTS: Sharp decrease of reduced glutathione level as well as increase of oxidated glutathione level were observed in all experimental animal species after intraperitoneal administration of plague "murine" toxin. Changes in levels of GSH and G-SS-G were followed with decrease of total glutathione level. Activity of glutathione peroxidase was decreased in mice and Mongolian gerbils. There was increase of activity of this enzyme in guinea pigs. Level of glutathione reductase was decreased in all studied animals. CONCLUSION: Performed studies allow to hypothesize that oxidation of thiolic functional groups in organisms of animals as a result of H2O2 generation has important role during plague intoxication (administration of sublethal doses of plague "murine" toxin).

[Hydrogen peroxide as an inductor of uncultivable state of Vibrio cholerae eltor in an experiment].

The influence of hydrogen peroxide on the dynamics of transition into uncultivable state (UCS) and on the reversion of V. cholerae and their subcultures, resistant to hydrogen peroxide, was studied. The transition of the initial cultures in river and distilled water into UCS took place earlier than that in resistant to hydrogen peroxide variants. The capacity for reversion to hydrogen peroxide resistant subcultures preserved, on the average, 2 - 3 times longer. An increase in the level of hydrogen peroxide in uncultivable populations was found to be 2.7 - 4.4 times. Subcultures, resistant to hydrogen peroxide, in the vegetative form had lower characteristics of peroxide concentrations than in uncultivable form (UCF), but somewhat higher than in initial variants. In revertants the concentration of hydrogen peroxide was lower in UCF, but somewhat higher than in vegetative cultures. The dynamics of the formation of UCF by cholera vibrios, with different degree of stability to the action of hydrogen peroxide, the accumulation of hydrogen peroxide in uncultivable populations, the deceleration of transition into uncultivable forms, an accumulation of hydrogen peroxide and an increase in the time of the reversion of clones, resistant to hydrogen peroxide, made it possible to suggest that the accumulation of hydrogen peroxide was possible to make an essential contribution to the formation of UCF of cholera vibrios in an experiment.

[Morphology and enzyme activity of nonculturable forms of Vibrio cholerae]. / Morfologiia i fermentativnaia aktivnost' nekul'tiviruemykh form cholernykh vibrionov.

The transition of V. cholerae into the uncultivable state under experimental conditions was accompanied by gradual changes in their morphology, motility and metabolic activity. The vibrios took the oval form, lost their flagellum, motility and enzyme activity on diagnostic media. Dehydrogenase activity tested by reduction of triphenyl tetrazolium chloride, increased at the initial stages and dropped to the initial level or even lower by the end of the observation period (10 months). Similar dynamics was noted when the cytoplasmatic marker enzyme--ATPase activity was studied. Glucose catabolism in the uncultivable forms shifted towards glycolysis. During 1-2 months ctx and tcp genes could be detected in these forms by the PCR. The dynamics of the biological properties under study made it possible to find out the existence of 3 functionally different stages in the development of an uncultivable population.

[Evaluation of hypoxic state in experimental animals induced by Yersinia pestis antigens]. / Otsenka gipoksicheskogo sostoianiia u éksperimental'nykh zhivotnykh pod vliianiem antigenov Yersiniia pestis.

Some characteristics of purine metabolism in experimental animals (white mice, clawed jirds and guinea pigs), injected intraperitoneally with Y. pestis "murine" toxin and capsular antigen (Fraction 1), were studied. Under the influence of sublethal doses of these antigens increased levels of guanine and xanthine in blood were noted. Changes in the content of xanthine oxidase in cells were insignificant. In white mice and clawed jirds the activity of succinate dehydrogenase decreased under the action of "murine" toxin and increased after the injection of Fraction 1.

[Characteristics of the acid-alkali equilibrium in blood of experimental animals in response to exposure of 'murine' toxin and Yersinia pestis capsular antigen]. / Pokazateli kislotno-shchelochnogo ravnovesiia krovi u éksperimental'nykh zhivotnykh pod vliianiem "myshinogo" toksina i kapsul'nogo antigena Yersinia pestis.

As revealed in this study, metabolic acidosis is observed in experimental animals the influence of "murine" toxin and Y. pestis fraction I, which is manifested by the parameters of the acid-base state, the gas composition of blood and the content of electrolytes.

[Effects of lipids obtained from the liver of marine animals on the immunologic status and hematologic indices of rats]. / Vliianie lipidov, poluchennykh iz pecheni morskikh zhivotnykh, na immunnyi status i gematologicheskie pokazateli u krys.

The influence of lipids received from liver of king crab (Paralithodes camtschatica) and liver of pollack on some indices of immunologic status of an organism and hematologic indices in rats was studied. The animals were divided into three groups in dependence from kind of lipid in diet: the control group received in the composition of lipid component of diet--lard and sunflower oil in the ratio 1:1, the second group--lard and lipid from pollack liver (1:1), the third group--lard and lipid from crabs liver (1:1). The differences of rations concerned their lipid component. The content of triglycerides in a liver of pollack compounded--73%, in a liver of crabs--50%, the content of phospholipids in a liver of pollack--12%, in a liver of crabs it is much more--20%; the total sun of omega-3 acids in the experimental group is practically identical: 23.8 and 23.1% accordingly. Some simulate influence of lipid from liver of crabs on the quantity of antibody forming cells of a spleen was noted. The tendency to decreasing of indices of humoral immunity was founded in rats, which received diet with lipid from liver of pollack. The decrease of the quantity of lymphocytes and the increase of the quantity of eosinophilic leukocytes in a peripheral blood of animals this group was noted in comparison with control and other experimental groups.

[The characteristics of the action of the capsular antigen of Yersinia pestis on cells from plague-susceptible and -insusceptible rodents]. / Nekotorye osobennosti deistviia kapsul'nogo antigena Yersinia pestis na kletki chuvstvitel'nykh i ne chuvstvitel'nykh k chume gryzunov.

The state of the functional activity of peritoneal leukocytes from different species of gerbils (Mongolian gerbils, Libyan jirds, as well as gerbils inhabiting the right and left banks of the Volga), exposed to the action of Y. pestis capsular antigen, has been found to correlate with the susceptibility of these animals to plague.

[The modulation of the function of the immunocompetent system and of nonspecific body resistance in rats with different ratios of essential fatty acids in the diet]. / Moduliatsiia sostoianiia immunokompetentnoi sistemy i nespetsificheskoi rezistentnosti organizma krys razlichnymi sootnosheniiami éssentsial'nykh zhirnykh kislot ratsiona.

The influence of dietary essential fatty acids on the immune functions and nonspecific resistance of male Wistar rats weighing 135.0 +/- 3.2 g was investigated after 3 months feeding. Rats were fed isocaloric purified diets containing 24% of fat (combinations of lard, sunflower oil and fish oil, eiconol, this providing the ratios of omega 6/omega 3 fatty acids equal to 1.1; 2.1; 6.1; and 49.0. An increase of immune responsiveness and nonspecific resistance in the groups fed diets with the minimal ratios of omega 6/omega 3 fatty acids as compared to that in rats fed a diet with ratio 49.0 was noted. Fatty acid analysis of peripheral lymphoid organs tissue lipids showed an increase in percentage of eicosenic omega 3 fatty acids in rats fed diets with increased content of polyunsaturated fatty acids omega 3.

[The participation of the neuraminidase of Yersinia pestis in the transmission of the transmembrane signal]. / Uchastie neiraminidazy chumnogo mikroba v peredache transmembrannogo signala.

Neuraminidase isolated from Yersinia pestis [correction of the plaque microbe] and purified has been studied for its effect on the peritoneal leukocytes of the white mice with results presented. Neuraminidase exerted the insulin-like effect on the peritoneal leukocytes of the white mice and this effect depended on the used dose. The priming of leukocytes by neuraminidase preparation was accompanied by the sharp increase of hydrogen peroxide production under effect of the capsule antigen of the plaque microbe and, apparently, by the appearance of additional binding sites for the adhesion piles of the plaque agent.

[Role of histamine receptors of mouse and guinea pig peritoneal leukocytes in the pathogenetic effect of Yersinia pestis adenylate cyclase]. / Rol' gistaminovykh retseptorov peritoneal'nykh leikotsitov myshei i morskikh svinok v realizatsii patogeneticheskogo deistviia adenilattsiklazy chumnogo mikroba.

The effect of purified preparation of adenylate cyclase isolated from Y. pestis on peritoneal leukocytes of white mice and guinea pigs was investigated. Y. pestis adenylate cyclase was shown to accomplish its pathogenic action via histamine-specific receptors on the surface of eukaryotic cells. The involvement of H1 and H2 histamine receptors on target cells in the adenylate cyclase action leading to development of plague infection is discussed.

[The effect of the adhesion pili of Yersinia pestis on the physiological activity of the leukocytes and macrophages in experimental animals]. / Vliianie pilei adgezii Yersinia pestis na fiziologicheskuiu aktivnost' leikotsitov i mekrofagov éksperimental'nykh zhivotnykh.

The data on the influence of the preparation of Y. pestis adhesion pili on peritoneal macrophages in white mice and guinea pigs are presented. Y. pestis adhesion pili have been found to induce the dose-dependent increase of cell chemiluminescence. They have also been found to induce a number of biochemical changes in target cells: the secretion of myeloperoxidase, an increase in the activity of cAMP-dependent protein kinases.

[The participation of the adrenergic receptors of the peritoneal leukocytes from white mice in the mechanism of the cellular control of the action of Yersinia pestis adenylate cyclase]. / Uchastie adrenergicheskikh retseptorov peritoneal'nykh leikotsitov belykh myshei v mekhanizme kletochnogo kontrolia deistviia adenilattsiklazy Yersinia pestis.

Y. pestis extracellular adenylate cyclase suppresses the oxidation metabolism of peritoneal leukocytes in white mice. The character of the modulating action of the enzyme in its interaction with the target cell infers the participation of adrenergic receptors.

[Evaluation of the modulating action of Yersinia pestis adenylate cyclase on guinea pig peritoneal leukocytes using chemiluminescence]. / Otsenka moduliruiushchego deistviia adenilattsiklazy chumnogo mikroba na peritoneal'nye leikotsity morskoi svinki s pomoshch'iu khemiliuminestsentsii.

The biological action of Y. pestis adenylate cyclase on peritoneal leukocytes of guinea pigs has been studied by means of chemiluminescence. Y. pestis adenylate cyclase is supposed to contribute to the "oxidation" explosion of phagocytes in plague.