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E V Grishina

Publications and source records attributed to E V Grishina.

17 recordsLinked to original sources
PubMed1992

Analysis of the causes of the suppression of oxidative phosphorylation and energy-dependent cationic transport into liver mitochondria of hibernating gophers, Citellus undulatus.

1. The causes of the suppression of oxidative phosphorylation and energy-dependent cationic transport into liver mitochondria of hibernating gophers have been analysed. 2. The decrease of the ATP synthesis rate and suppression of the energy-dependent K(+)- and Ca(2+)-transport into mitochondria during hibernation has been found to be mainly related to a delta psi decrease in mitochondria of hibernating gophers. 3. The increase delta psi upon incubation of the mitochondria of hibernating animals in a hypotonic medium results in an essential acceleration of ATP synthesis and energy-dependent cationic transport.

Adenosine Triphosphate↗
PubMed1991

[Incompatibility and replication of plasmids].

The identified basic replicons rep1 and rep2 of plasmid pAP42 belong to different groups of incompatibility (inc FIX and inc FVIII). The replicons are partly incompatibile with other inc F-groups too. The results indicate connection between plasmid incompatibility and their replication.

DNA Restriction Enzymes↗
PubMed1991

[Activation of oxidative phosphorylation and energy-dependent absorption of Ca2+ and K+ ions by liver mitochondria of hibernating ground squirrels in hypotonic media].

Activation of initially suppressed oxidative phosphorylation and energy-dependent uptake of Ca2+ and K+ ions by liver mitochondria of hibernating gophers which is prevented by phospholipase A2 inhibitors, has been shown to occur in hypotonic media. Partial inhibition of the respiratory chain of liver mitochondria of active gophers by antimycin A which causes a decrease in the uncoupled respiration rate and delta psi down to values typical of mitochondria of hibernating gophers, practically exactly reproduced the suppression of oxidative phosphorylation and energy-dependent uptake of cations observed during hibernation. It was concluded that partial deenergization arising as a result of inhibition of the respiratory chain is the main and unique cause of suppression of energy-dependent functions of liver mitochondria of hibernating gophers.

Adenosine Triphosphate↗
PubMed1990

[The effect of medium tonicity on the rate of respiration and oxidative phosphorylation in liver mitochondria of active and hibernating ground squirrels].

The rate of respiration and ATP synthesis in liver mitochondria (M) isolated from hibernating ground squirrels and incubated in the medium with normal tonicity (250 mosm) was shown to be considerably lower than the rate of respiration and ATP synthesis in liver M from active animals. The increase of the medium tonicity to 600 mosm simulated the state of M from hibernating animals, resulting in a decrease of the respiration rate of M from active ground squirrels. On the contrary, the decrease of the tonicity to 60 mosm caused the activation of the respiration and increase of the ATP synthesis in M from hibernating ground squirrels. Bromophenacylbromide (BPhB), an inhibitor of phospholipase A2, prevented the activation of the respiration of M from hibernating animals incubated in the medium with low tonicity. BPhB had practically no effect on the respiration of M from both hibernating and active ground squirrels as well as on the swelling of M in hypotonic medium. It was concluded that the activation of the respiration and increase of the ATP synthesis rate in M from hibernating ground squirrels incubated in the medium with low tonicity is related to the activation of phospholipase A2. It was assumed that decrease of phospholipase A2 activity and change in the lipid composition of mitochondrial membrane may be one of the reasons for inhibition of the respiration rate in M from hibernating ground squirrels.

Adenosine Triphosphate↗
PubMed1989

Regulation of the rate of respiration and oxidative phosphorylation in liver mitochondria from hibernating ground squirrels, Citellus undulatus.

1. The rates of oxidation of various substrates (beta-hydroxybutyrate, succinate, ascorbate + TMPD) and the rate of ATP synthesis in liver mitochondria from active and hibernating ground squirrels were measured. 2. It was shown that the rate of mitochondrial respiration is significantly lower in hibernating animals than in active animals. 3. The degree of inhibition of mitochondrial respiration in hibernating ground squirrels was found to correlate with the length of the respiratory chain fragment involved in the oxidation of a given substrate. 4. The inhibition of mitochondrial respiration in hibernating animals was accompanied by a decrease in the rate of ATP synthesis. 5. The activity of phospholipase A2 in liver mitochondria from hibernating ground squirrels was found to be decreased. The activation of phospholipase A2 by Ca2+ ions eliminated the inhibition of respiration almost completely. 6. It was assumed that the inhibition of mitochondrial respiration during hibernation is (a) related to the suppression of phospholipase A2 activity and (b) caused by the reduced rates of electron transport through the respiratory chain and/or of substrate transport across the mitochondrial membrane.

Adenosine Triphosphate↗
PubMed1989

[Phospholipase A activity determines the rate of respiration of the mitochondria in hibernating animals].

The mechanisms for regulating the rate of respiration and oxidative phosphorylation in liver mitochondria from hibernating ground squirrels were studied. The microviscosity of the mitochondrial membrane in hibernating squirrels was found to be higher than that in active animals. Probably, a high microviscosity of the membrane causes a decreases in the rate of the transport of oxidation substrates into the mitochondrial matrix, which in turn may be one of the main reasons for the inhibition of mitochondrial respiration in hibernating squirrels. The activation of phospholipase A2 in a hypotonic medium results in the acceleration of the respiration and phosphorylation in the mitochondria from hibernating squirrels and is accompanied by the increase of the transport of substrates across the mitochondrial membrane. The inhibition of phospholipase A2 decreases Ca2+--induced acceleration of the transport of substrates and prevents the activation of the respiration and phosphorylation in a hypotonic medium.

Animals↗
PubMed1986

Depression of neuron responses to acetylcholine by combined application of norepinephrine and substrates of the tricarboxylic acid cycle.

The possible relationship between the function of nicotinic acetylcholine receptors in Lymnaea stagnalis neurons and energy metabolism was studied. Oxidative phosphorylation was activated by treatment of neurons with substrates of the tricarboxylic acid cycle and norepinephrine. Transmembrane currents induced by acetylcholine in isolated neurons were measured by voltage clamp. Succinate dehydrogenase activity was determined histochemically in the same neurons. Cyclic adenosine monophosphate concentration in ganglia were assayed by the protein saturation method of Gilman (1970). When used alone, succinate depressed the responses of about 50% of neurons to acetylcholine. Norepinephrine did not affect the acetylcholine-induced currents but almost doubled the inhibitory action of succinate. The mixture of norepinephrine and isocitrate also diminished the responses to acetylcholine but to a lesser extent than norepinephrine with succinate. A short-term exposure of the ganglia to succinate with norepinephrine led to the activation of succinate dehydrogenase in neurons and a threefold increase in cyclic adenosine monophosphate concentrations in ganglia. When used alone, norepinephrine doubled the cyclic adenosine monophosphate concentration. The results obtained suggest energy-dependent regulation of acetylcholine receptors.

Acetylcholine↗
PubMedDate not supplied

[Anaerobic formation of succinate and facilitation of its oxidation -- possible mechanisms of cell adaptation to oxygen deficiency].

An important role of anaerobic formation of succinate in anoxic and hypoxic states and the activation of succinate oxidation under hypoxia were shown. It was concluded that, for maintaining the energetics of animal cells under conditions of oxygen deficiency, it is advisable to use substrates capable of participating in the anaerobic formation of succinate, whereas under hypoxia it is reasonable to use succinate itself.

Adaptation, Biological↗
PubMedDate not supplied

[Evaluation of glucose utilization in patients with insulin-independent diabetes mellitus by using breathing test].

Commonly used clinical and biochemical parameters, such as the content of glucose, insulin, somatotropic hormone, triglycerides, lactate, pyruvate, and free fatty acids (FFA) in blood of practically healthy subjects and in patients with insulin-independent diabetes mellitus (IIDM), were compared with the parameters obtained by mass-spectrometric analysis of 13CO2 in expired air after 13C-glucose loading. It was shown that, as opposed to healthy subjects, the content of blood glucose and free fatty acids in patients with IIDM increased, the level of glucose dropped in progression upon short-term fasting, and the concentration of lactate changed both upon fasting and after the administration of small test doses of glucose. The use of the 13C-glucose breathing test (13C-GBT), which presupposes the loading of safe small doses of glucose enriched in 13C-isotope permitted one to reveal a number of novel quantitative diagnostic criteria for the evaluation of glucose metabolism in patients with IIDM: a decrease in the rate of 13C withdrawal as a constituent of expired carbon dioxide after the administration of 13C-glucose; a reduction in the amount of exogenous glucose metabolized to carbon dioxide; and increased oxidation of endogenous substrates participating in carbon dioxide formation. Small glucose loads proposed by the authors in 13C-GBT are safe for patients with diabetes mellitus and have no effect on the level of blood glucose in healthy persons. The parameters determined by noninvasive 13C-GBT are more sensitive for diagnosis than commonly used biochemical characteristics of blood in patients with IIDM. The diagnostic criteria obtained allow the prediction of the maximum prohibited glucose loading for every patient.

Adult↗
PubMedDate not supplied

[The intensity of oxidative phosphorylation and the function of the adenylate system in the liver mitochondria of active and hibernating susliks Citellus undulatus].

The state of adenylate system and intensity of oxidative phosphorylation in liver mitochondria of active and hibernating ground squirrels were studied depending on the concentration of extramitochondrial Ca2+ ([Ca2+]ex). It was shown that at [Ca2+]ex.10(-7) M, the content of ATP as well as ATP/ADP ratio are slightly lower in the mitochondria of hibernating ground squirrels than in the mitochondria of active animals. The other parameters of the adenylate system under the same conditions differ insignificantly. [Ca2+]ex increase to 10(-6) M has little effect on the parameters of the adenylate system of active animals. On the contrary, the mitochondria of hibernating ground squirrels are strongly affected: the level of ATP is 1.5-fold and the ratio of ATP/ADP is almost 2-fold decreased. At both [Ca2+]ex the intensity of oxidative phosphorylation is essentially higher in the mitochondria of active ground squirrels. With increasing [Ca2+]ex the rate of ATP synthesis decreases, and in the mitochondria of hibernating animals the decrease is more pronounced than in the mitochondria of active animals. Thus, oxidative phosphorylation and adenylate system of mitochondria from hibernating ground squirrels are more sensitive to [Ca2+]ex increase than those of the mitochondria of active animals.

Adenosine Diphosphate↗
PubMedDate not supplied

[The use of sodium chloride baths in the treatment of diabetic patients with micro- and macroangiopathies].

Patients suffering from insulin-dependent or non-insulin-dependent diabetes mellitus with micro- and macroangiopathy took sodium chloride baths of diverse concentration (30 and 50 g/l). A control group consisted of patients who had taken "neutral" baths. The response to sodium chloride baths was registered in carbohydrate and lipid metabolism, microcirculation, hemorheology, lower limbs circulation, exercise tolerance. Baths with sodium chloride concentrations 50 g/l have advantages, especially in patients with insulin-dependent diabetes mellitus.

Adolescent↗