[The use of the method of anomalous time dependence of viscosity for registration of changes in the nucleoide conformation. Part 1].

The sensitivity of the method of anomalous time dependence of viscosity to changes in the conformation of DNA-protein complexes (such as nucleoide) by the action of increased temperature (33, 70 and 85 degrees C) and the combined action of temperature and Na+, Cl- ions on lysates of Escherichia coli AB1157 cells has been studied. The optimal conditions of the cell lysis was determined on the basis of the curve parameters of the anomalous time dependence of viscosity.

Prooxidant-antioxidant balance in animals with enhanced hemoglobin-oxygen affinity under acute normobaric hypoxia.

The content of main lipid peroxidation (LPO) products and antioxidant defense (AD) factors were investigated in rats without a treatment and with preliminary rise of hemoglobin-oxygen affinity (HOA) by cyanate under acute normobaric environmental hypoxia. Under acute hypoxia the cyanate-treated rats expressed the lower contents of conjugated dienes (CD), thiobarbituric acid-reactive substances (TBARS), Schiff bases (SB) and higher alpha-tocopherol (alpha-T) concentration, and catalase (CAT) activity than in control animals (mainly in tissues). The regression analysis of HOA, LPO and AD parameters in investigated material indicated the close positive correlations of oxygen pressure for hemoglobin half-saturation (p50) with CD, TBARS, and SB, and negative correlation of p50 with alpha-T and CAT.

[Method of the anomalous time dependence of viscosity for registration of changes in conformational state of Escherichia coli cell genome].

The sensitivity of the anomalous time dependence of viscosity to the concentration of the DNA-protein complexes (DNA + histone-like proteins of bacteria or, in other words, the genome) such as chromatin and the conformations of these complexes in lysates of E. coli AB1157 cells were studied. A linear region of the anomalous viscosity time dependence on the concentration of E.

[The role of the oxygen-binding properties of the blood in maintaining pro-oxidant-antioxidant equilibrium in the body].

Tissue pro-oxidant generation under standard conditions is equilibrated with the activity of intra- and extracellular antioxidants; thus some optimal level of pro-oxidant-antioxidant balance is created. Oxygen-dependent nature of lipid peroxidation processes implicates its complex multilevel regulatory system, where systemic mechanisms may dominate upon the intracellular ones. This suggests a necessity in the investigation of body oxygen transport not only in terms of the requirements of energetic metabolism in electron acceptor but also as a physiological mechanism for antioxidant defense and, in general, as the mechanism involved in a maintenance of pro-oxidant-antioxidant balance.

The effect of NO synthase inhibition on blood oxygen-carrying function during hyperthermia in rats.

Hyperthermia is known to be accompanied by considerable worsening of body oxygen delivery. Nitric oxide (NO) is a messenger that contributes to the regulation of oxygen transport (vasodilation, formation of nitrosohemoglobin, erythrocyte deformability), but also has cytotoxic effects (when abundantly generated by inducible NO synthase and through a formation of peroxynitrite). The effects of NO synthesis inhibition on the blood oxygen transport (hemoglobin-oxygen affinity and erythrocyte deformability) were investigated in rats with hyperthermia.

[The effect of NO-synthase inhibition on the blood oxygen transport function during fever in rabbits].

I.v. administration of NG-nitro-L-arginine attenuated a fever response in rabbit.

Fe(2+)-initiated chemiluminescence in rats with high hemoglobin-oxygen affinity during fever.

The effect of high hemoglobin-oxygen affinity (HOA) on chemiluminescence initiated by Fe2+ was studied in rat plasma and red cell ghosts during fever. The high HOA was induced by daily ingestion of sodium cyanate with drinking water for 8 weeks. Rats with high or normal HOA received i.

[An analysis of the changes in the basic parameters of lipid peroxidation and blood oxygen-transport function in pyrogenal-induced fever].

Content of main products of lipid peroxidation and hemoglobin affinity to oxygen were determined in mixed venous blood of rabbits during pyrogenal fever. Their relationships were studied on the basis of the factor analysis. The model of group structure of these parameters was obtained.

Analysis of the relationship between hemoglobin-oxygen affinity and lipid peroxidation during fever.

Endogenous hyperthermia was induced in rabbits by i.v. pyrogenal administration.

[The effect of sodium cyanate-modified hemoglobin oxygen affinity on the heat resistance of rats].

Regression analysis of relationship between rat hemoglobin-oxygen affinity (HOA) and rectal temperature has shown a close positive correlation of these parameters. Heat resistance (HR) was examined in rats with HOA elevated by sodium cyanate in order to recognize the contribution of HOA to a process of body heat adaptation. Our data suggest that HR of treated rats was larger than in control animals.

[The role of oxygen-binding properties of hemoglobin in the development of oxygen deficiency in acute exogenous hyperthermia].

Acid-base balance and oxygen-binding hemoglobin properties in mixed venous blood have been studied in 25 mongrel rabbits with acute environmental hyperthermia. As oxygen-hemoglobin affinity at standard pH, pCO2 and temperature increases, the effect of heat on oxygen-hemoglobin interaction is considerably attenuated. The Bohr effect increases.

[Oxygen transport function of the blood in hyperthermia in rabbits].

After 30-min or longer incubation of rabbit blood under 42 degrees C the blood O2 affinity was increased. During governed hyperthermia of conscious rabbits PO2, pH and the oxygen content in the mixed venous blood were decreased. Similar events were observed after 1 hour from the ceasing of hyperthermia.

[Hemoglobin affinity for oxygen in the blood draining from the heart].

The difference in hemoglobin affinity for oxygen in blood of the coronary sinus and in mixed venous blood was shown in dog experiments. The lower affinity of hemoglobin for blood flowing from the heart causes greater deoxidation of oxyhemoglobin. Following injection into the body of adrenaline which activates the adenylyl cyclase system, the oxyhemoglobin dissociation curve of coronary sinus blood is displaced to the left.