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1.
Biochemistry (Mosc) ; 68(9): 1002-5, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14606943

RESUMO

The effect of carnosine on self-organization of mitochondrial assemblies was studied in rat liver homogenate of quiescent and excited animals. It was shown in separate electron microscopy experiments with serial slices that under our conditions of preparation of homogenate, blocks of native mitochondrial-reticular network in the cell, assemblies of mitochondria, are kept. Carnosine was shown to prevent dissociation of assemblies during storage. Its effect is maximal for more dissociated assemblies from excited animals with decreased ability for self-organization. Prevention of disassembly of organelles by carnosine can serve as one of the mechanisms of carnosine-induced diminishing of muscle fatigue under prolonged work.


Assuntos
Carnosina/farmacologia , Fígado/citologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Animais , Epinefrina/farmacologia , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Masculino , Mitocôndrias Hepáticas/ultraestrutura , Ratos , Ratos Wistar
2.
Mitochondrion ; 3(2): 67-73, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16120345

RESUMO

The role of impairment of general oxidative and energy metabolism in pathogenesis of lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH) and their correction by (1-adrenoblocker alfuzosin was studied. One group of patients (N = 126) was examined by standard methods for determination of the severity of LUTS by IPSS and mean effective volume of urinary bladder (MEVUB). In the second group (N = 29) in addition to functional examinations, metabolic indicators in blood were measured: antioxidant activity (AOA) and succinate dehydrogenase activity (SDA). Severity of LUTS depends greatly on the MEVUB. It was the first to show a practically complete correlation between LUTS, AOA and SDA. Severity of LUTS exactly correlates with indicators of oxidative and energy metabolism. In patients with more heavy LUTS, lowest AOA and SDA values were found. In the course of effective treatment, both phenomena developed an improvement of clinical symptoms and a rise of biochemical parameters. Close correlation between functional and metabolic phenomena is evidence of an essential role of metabolic mechanisms in the pathogenesis of LUTS with BPH. This opens perspectives to use antioxidants and energy metabolism activators for correction of UB dysfunction in patients with BPH.

3.
Mitochondrion ; 1(3): 249-67, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16120282

RESUMO

A protocol is developed for preparation of concentrated rat liver homogenate preserving assemblies of mitochondria in isotonic KCl under 0 and 15 degrees C. Assemblies preserve ability for self-organization during storage in homogenate. All key energy functions of mitochondria can be investigated in such a homogenate. Oxidative phosphorylation and membrane potential are stable for 5-7 h and can be still observed on the next day. Substrate-level phosphorylation is better pronounced for mitochondria in KCl than in sucrose medium while Ca2+ capacity is greater and lipid peroxidation is much lower. Sucrose addition impairs these functions. The rate of phosphorylating respiration is lower in large assemblies and higher in small. Transition from large to small assemblies corresponds to the transition from quiescent state of animal to adrenaline induced active state. The proposed method is particularly convenient for clinical investigations with small bioptates.

4.
Biofizika ; 45(1): 83-8, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10732215

RESUMO

A convenient model for studying the mechanisms of biological self-organization is described by morphometric investigation of formation of mitochondrion associations in medium containing physiological concentration of potassium ions without nonpolar substances. Association formation was considerably better at 15-18 degrees C during isolation and storage than at 0 degree C. The existence of filamented mitochondria in homogenate was also shown by staining of succinate dehydrogenase. Formation of associations increased in medium pretreated with negative air ions carrying superoxide and is probably due to hydrogen peroxide. The effect of substances influencing the surface charge on association formation was studied.


Assuntos
Mitocôndrias Hepáticas/ultraestrutura , Ar , Animais , Técnicas In Vitro , Íons , Masculino , Mitocôndrias Hepáticas/enzimologia , Potássio , Ratos , Ratos Wistar , Succinato Desidrogenase/metabolismo , Superóxidos , Temperatura
6.
Biochemistry (Mosc) ; 62(2): 129-37, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9159864

RESUMO

Mitochondria in the form of associations close to their state in the quiescent cell were obtained in rat liver homogenate under physiological for cytosol concentrations of potassium and calcium ions and small dilution of tissue. Associations in such homogenates are stable on storage in ice for several hours. Dissociation of associations is induced by dilution of the homogenate, addition of EDTA, or by administration of adrenaline to the animal. Respiration rate is increased and ADP/O ratio is decreased when associations dissociate. The observed increase in respiratory rate induced by adrenaline administration in vivo is decreased or abolished when associations are dissociated in the incubation medium induced by influences in vitro. This is due to hyperactivation of respiration which leads to inhibition of succinate oxidation by oxaloacetate. Under the conditions preserving the associations of mitochondria a close interaction of oxidative and transamination processes is observed as well as a broader range of metabolic states of mitochondria than in standard preparations which dissipate into single granules on isolation in sucrose, high dilution, and washing.


Assuntos
Mitocôndrias Hepáticas/metabolismo , Consumo de Oxigênio , Ácido Amino-Oxiacético/farmacologia , Animais , Cálcio/metabolismo , Ácido Egtázico/farmacologia , Técnicas In Vitro , Cinética , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/ultraestrutura , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar
7.
Biochemistry (Mosc) ; 62(10): 1089-95, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9461630

RESUMO

The effect of negative air ions generated by a Tchijevsky lustre was studied in rat liver mitochondria in homogenate under conditions providing preservation of their native structural organization in the form of associations. Rapid formation of large associations from intermediate and small associations occurs after the homogenate was put into medium pretreated by negative air ions (NAI). Under the influence of a flow of NAI on mitochondria stored on ice for 2-3 h formation of giant associations is observed. Associations of mitochondria are not dissipated by stirring with a magnetic stirrer for several minutes. The influence of medium pretreated with NAI or flow of NAI on homogenate improves weakened respiratory energy control and restores stimulation of phosphorylating respiration by adrenalin administration. The improvement of phosphorylation in mitochondria by NAI is perhaps caused by more complete preservation of both their native structural organization and related physiological regulation of mitochondrial processes in isolated preparations.


Assuntos
Mitocôndrias Hepáticas/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Superóxidos/farmacologia , Animais , Epinefrina/administração & dosagem , Epinefrina/farmacologia , Masculino , Microscopia de Contraste de Fase , Mitocôndrias Hepáticas/ultraestrutura , Fosforilação/efeitos dos fármacos , Ratos
8.
Biofizika ; 32(2): 313-22, 1987.
Artigo em Russo | MEDLINE | ID: mdl-3034336

RESUMO

Studies were carried out of the physical mechanism of biological effect of natural stimulant of the living activity--light negative hydroaeroions. The latter are a hydroxyl separated from water ions and designated here as electrically noncompensated hydroxyl OH-. Unique effect of OH-, i.e. fast restoration and prevention of fine damage of native mitochondria (NM) at storage was revealed on mitochondria preparations by specific procedure, providing preservation of the ability of self-organization--formation of aggregated and denser packing--native mitochondria. This effect of OH- is conditioned by increased formation of native mitochondria aggregates and is concerned with better ADP phosphorylation and Ca2- release. The effect of the air current OH- is produced by water action presaturated with OH-. OH- induces in water cooperative structure formation preserved for many days, which is indicated by an increase of its heat capacity and decrease of surface tension. The principal factor in OH- effect both on mitochondria and water seems to be a decrease of local positive changes. It is of more advantage in NM water suspensions to order (structurate) NM with disordering water, which explains formation of NM stable aggregates. OH- effect supports the main function of the organism struggling with proton excess which destroys biological self-organization. Strengthened structural self-organization under the effect of OH- found in NM seems to be of universal importance for biological macromolecules and membranes and is a primary effect of OH- on the living objects.


Assuntos
Hidróxidos/farmacologia , Mitocôndrias/metabolismo , Animais , Transporte Biológico , Encéfalo/metabolismo , Radicais Livres , Técnicas In Vitro , Substâncias Macromoleculares , Mitocôndrias Hepáticas/metabolismo , Consumo de Oxigênio , Prótons , Ratos , Água
12.
Biokhimiia ; 42(6): 1030-44, 1977 Jun.
Artigo em Russo | MEDLINE | ID: mdl-196685

RESUMO

A mathematical model is proposed to describe the behavior of the pyruvate metabolic reactions, Krebs cycle and oxidative phosphorylation over a wide range of changes in the pyruvate influx rate and the activities of ATPase and NADH-reoxidating dehydrogenase. The role of adenine and pyridine nucleotides in various allosteric regulations of the Krebs cycle enzymes is discussed. The accumulation of ATP and NADH has been shown to proceed in definite succession, which makes the allosteric regulation of the Krebs cycle enzymes successive too. First "works" the inhibition by ATP, then by NADH. It has been shown that the properties of the model are in qualitative agreement with the experimental data (Garber A., Hanson R. [1]) on pyruvate oxidation by mitochondria from guinea pig liver, when allosteric regulation of isocitrate dehydrogenase by adenine nucleotides is taken into account.


Assuntos
Nucleotídeos de Adenina/fisiologia , Ciclo do Ácido Cítrico , Mitocôndrias Hepáticas/metabolismo , NAD/fisiologia , Piruvatos/metabolismo , Adenosina Trifosfatases/metabolismo , Regulação Alostérica , Animais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Cobaias , Isocitrato Desidrogenase/metabolismo , Matemática , Mitocôndrias Hepáticas/enzimologia , Modelos Biológicos , NADH NADPH Oxirredutases/metabolismo , Oxirredução
13.
Mikrobiologiia ; 45(1): 157-60, 1976.
Artigo em Russo | MEDLINE | ID: mdl-940489

RESUMO

Gas chromatography is used to determine the specificity of microbial esterases in vivo. The technique is based on hydrolysis by the cells of esters of fatty acids containing different alcohol groups. The specificity was evaluated by means of the coefficient Kc which changed from 0 to 1 and did not depend on the time of hydrolysis. The esterases of M lysodeicticus were more specific than the esterases of S. marcescens by a factor of 30 during hydrolysis of the equimolar mixture of methyl ester of pelargonic acid and ethyl ester of caprylic acid. This criterium of specificity may be used for rapid identification of bacteria.


Assuntos
Bactérias/enzimologia , Esterases , Catálise , Cromatografia Gasosa , Ácidos Graxos
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