[Structure-functional status of the erythrocyte membrane in acute poisoning by metaphos and administration of perftoran]. / Strukturno-funktsional'nye sostaoiane membran éritrotistov pri ostrovom otravlenenii metafosom i vvedenii perftorana.

The effect of perftoran administration on structure-functional state of erythrocyte membrane was investigated under conditions of metaphos intoxication. Metaphos administration at the dose of LD50 caused pronounced membrane-toxic effect. Perphtoran administration to animals reduced manifestation of the membrane damage.

[Effect of ionizing radiation and physical loads on pyrimidine-5'-nucleotidase activity in rat liver subcellular fractions]. / Vliiane ioniziruiuschei radiatsii i fizicheskoi nagruzki na aktivnost' pirimidin-5'-nukleotidazy v subkletochnykh fraktsiiakh pecheni krys.

Activity of pyridine-5'-nucleotidase in the mitochondria and postmitochondrial supernatant of the rat liver has been studied as affected by the radiation and physical load (running till tiredness). It is shown that physical load leads to double increase of cytidinemonophosphatase activity and does not actually affect uridine monophosphate one. Irradiation evokes changes of cytidine monophosphatase activity of the studied fractions in time: 1 year after irradiation it increases by 45%, 1 day later it sharply changes and 3 days later it increases again. Mutual action of the irradiation and physical loading 1 year after the irradiation causes the decrease of uridine monophosphatase and cytidine monophosphatase activity and 3 days later their amount increases, especially in the postmitochondrial supernatant (2-53 times). Thus the data obtained show that the effect of the radiation and physical loading evoke rather essential and stable changes in the activity of key enzymes of uridine monophosphate and cytidine monophosphate.

[The effect of ionizing radiation and physical loading on the molecular heterogeneity of nucleoside phosphate kinases in liver subcellular fractions]. / Vliianie ioniziruiushchei radiatsii i fizicheskoi nagruzki na molekuliarnuiu geterogennost' nukleozidfosfatkinaz v subkletochnykh fraktsiiakh pecheni.

The different molecular forms of nucleoside-monophosphate kinases (KF 2.7.4.4) and nucleoside-diphosphate kinases (KF 1.7.4.6) which are responsible for the final steps of pyrimidine nucleotide synthesis were determined in mitochondrial rat hepatic supernatant under condition of combined influence of X-ray and maximum physical exercises (running up to complete exhaustion). The maximum activity of investigated nucleosidediphosphate kinases were observed in intact animals in that fractions which were eluted with tris-HCl buffer solution (0.075 and 1.0 M, pH 7.4). X-ray radiation and physical exercises caused the deviation of chromatographic data of maximal enzymatic activities. The drastic lowering of investigated enzymes was observed after X-ray irradiation and maximum physical exhaustion. This fact is in favour for the suppression of the final steps of primidine nucleotides synthesis under explored conditions of experimental investigations.

[Activity of alanine- and aspartate-aminotransferases in organs of albino rats subjected to whole body gamma-irradiation and physical exercise]. / Issledovanie aktivnosti alanin- i aspartataminotransferaz v organakh belykh krys pri total'nom gamma-obluchenii i fizicheskoi nagruzke.

The investigations of enzyme activity such as aspartate aminotransferase (AST, KE 2.6.1.1.) and alanine aminotransferase (ALT, KE 2.6.1.2) playing an important role in proteins metabolism were carried out in cell fraction of rat liver, myocardial and skeleton muscle after the influence of ionizing radiation (6 Gy) and the maximum physical loading. It was shown that physical loading furthered the increase of ALT-activity in all cell fractions except liver cytosol. And it was noted a strongly pronounced tendency of AST-activity to lowering, except muscle cell fractions. ALT-activity level in irradiated animals showed phase changes dependent on the term of observation and the kind of investigated tissues. The primary lowering of AST-activity in cell fractions of the investigated tissues is a conformity to natural laws of the gamma-irradiation influence on AST in most cases. It was shown that the physical tiredness made worse penetrated radiation action on the investigated enzymes.

[Effect of pyridoxal phosphate on the activity of aminotransferases in different structure-functional regions of the rabbit brain in radiation sickness]. / Vliianie piridoksal'fosfata na aktivnost' aminotransferaz v razlichnykh strukturno-funktsional'nykh otdelakh golovnogo mozga krolikov pri luchevoi bolezni.

Pyridoxal enzymes of transamination (aspartate aminotransferase, KF 2.6.1.1. and alanine aminotransferase, KF 2.6.1.2) have been studied for their activity in different departments of the rabbit brain under the effect of ionizing radiation and introduction of pyridoxal phosphate. It has been established that the effect of ionizing radiations does not evoke the change in aspartate aminotransferase and alanine aminotransferase activity in different structure-functional departments of the rabbit brain, the decrease of aminotransferases activity in the acute period of the radiation sickness being natural. Introduction of pyridoxal phosphate irradiated animals promotes relative normalization of activity of the enzymes under study.

[Effect of pyridoxal phosphate on gamma-aminobutyric acid metabolism in different sections of the brain in irradiated animals]. / Vliianie piridoksal'fosfata na obmen gamma-aminomaslianoi kisloty v razlichnykh otdelakh golovnogo mozga obluchennykh zhivotnykh.

A study was made of the effect of X-rays (4,5 Gy) and pyridoxal phosphate (3 mg/kg, v/v) on the activity of pyridoxal enzymes of GABA metabolism (e.g. glutamate decarboxylase, E.C. 4.1.1.15) and aminobutyrate aminotransferase (GABA-T, E.C. 2.6.1.19), as well as on GABA and glutamate content of the hemisphere cortex, brain stem and cerebellum of rabbits 6 and 10 days following irradiation and injection of a coenzyme. The height of the radiation sickness in rabbits was characterized by the manifest changes in glutamate decarboxylase and GABA-T activity, as well as in GABA and glutamate content of various brain parts differing in the structural and functional functions. The administration of pyridoxal phosphate produced pronounced activation of glutamate decarboxylase, particularly 6 days after irradiation and administration of the co-enzyme, and, to a lesser extent, influenced GABA-T function. Pyridoxal phosphate favored maintaining the GABA level above the control level in the hemisphere cortex and brain stem 6 and 10 days after exposure. The injection of pyridoxal phosphate did not normalize the glutamate content of the brain parts 6 days after exposure, but favored the normalization of GABA-T activity on day 10.

[Pyridoxal phosphate as an agent for normalizing the monoamine oxidase activity of the brain in radiation sickness]. / Piridoksal'fosfat kak sredstvo normalizatsii monoaminoksidaznoi aktivnosti golovnogo mozga pri luchevoi bolezni.

A study was made of the influence of the coenzyme pyridoxal phosphate on the activity of mitochondrial monoaminoxidase (MAO) catalyzing oxidative deamination of serotonin at the exacerbation of acute radiation disease (on the 6th day after radiation exposure) in different parts of the brain (cerebral hemisphere, stem and cerebellum). Experiments were staged on rabbits, irradiated by x-ray at a dose of 4.5 Gy with a dose rate of 0.33 Gy/min. The peak of radiation disease was characterized by considerable changes in MAO activity resulting in catalysis of oxidative deamination of serotonin in different parts of the brain and in different mitochondrial subfractions. Pyridoxal phosphate produced a positive effect on monoaminoxidase activity, catalyzing serotonin deamination, and as a coenzyme it can be incorporated in a complex of drugs used for normalization of metabolism of mediators of the nervous system as well as for therapy of radiation injuries.

[Monoamine oxidase activity in gastrointestinal tract tissues of animals after irradiation and administration of pyridoxal phosphate]. / Monoaminoksidaznaia aktivnost' tkanei zheludochno-kishechnogo trakta zhivotnykh posle oblucheniia i vvedeniia piridoksal'fosfata.

The X-ray irradiation in a dose of 450 R is shown to decrease the monoaminoxidase activity in the cell fractions of the mucous membrane of small intestine as against the fractions of the stomach mucosa. The administration of pyridoxalphosphate to the irradiated rabbits increases the monoaminoxidase activity in the fraction and subfractions of small intestine mucosa mitochondria, but the enzyme activity being compared with the control group has a tendency to decrease.

[Changes in the level of pyrimidine nucleoside phosphates in the liver of irradiated rats]. / Izmeneniia soderzhaniia pirimidinovykh nukleozidfosfatov v pecheni obluchennykh krys.

Content of uridyl and cytidyl nucleoside-phosphates in the liver of rats irradiated by gamma-rays (60Co) in a dose of 774 mC/kg (3000 P) was studied 0.5, 1, 3, 6 and 24 h after the effect. A trustworthy decrease of UTP and CTP as well as UDP and CDP content 24 h after irradiation was found. The number of pyrimidine nucleoside monophosphates increases after 24 h of the effect.

[Catabolism of pyrimidine nucleotides in the liver of irradiated animals]. / Issledovanie katabolizma pirimidinovykh nukleotidov v pecheni obluchennykh zhivotnykh.

A study was made of the activity of nucleoside diphosphatase (NDPase, EC 3.6.1.16) and nucleoside triphosphatase (NTPase, EC 3.6.1.15) that catalyze enzymatic dephosphorylation of UDP, CDP, UTP, and CTP in mitochondria and postmitochondrial supernatant fraction of rat liver 30 min, 1, 3, 6 and 24 h following 60Co-gamma-irradiation with a dose of 774 mC/kg. The observed phase changes in the enzyme activity depended on the times of exposure, a cell fraction, and nucleotides under study. Both uridylic and cytidylic nucleotides exhibited a significant increase in the their enzymatic disintegration being more pronounced at a comparatively later times, that is, 6 h, and particularly, 24 h after irradiation.

[Nucleoside mono- and nucleoside diphosphate kinase activities in rat liver and brain in radiation sickness]. / Nukleozidmono- i nukleoziddifosfatkinaznaia aktivnost' pecheni i golovnogo mozga krys pri luchevoi bolezni.

Activity of nucleoside di- and nucleoside triphosphates metabolism enzymes in tissues of rats gamma-irradiated by a dose of 30 Gy was studied 0.5, 1, 3, 6 and 24 hours after the radiation effect. It is shown that the nucleoside monophosphate kinase activity of the liver and brain is enhanced almost at all stages of the studies and the nucleoside diphosphate kinase activity is inhibited. A significant but reversible decrease of the nucleoside monophosphate kinase activity is observed in the liver 3 h later. By an end of the first day after irradiation the nucleoside mono- and nucleoside diphosphate kinase activities increase significantly both in the liver and brain.

[Early changes in the nucleoside diphosphate kinase activity of the rat brain and liver during whole body gamma irradiation in an absolutely lethal dose]. / Rannie izmeneniia nukleoziddifosfatkinaznoi aktivnosti golovnogo mozga i pecheni krys pri obshchem gamma-obluchenii v absoliutno letal'noi doze.

Nucleoside diphosphatkinase activity in mitochondria and post-mitochondrial supernatant fraction from brain and liver tissues was shown to decrease sharply during the first 60 min after total-body gamma-irradiation of rats with an absolutely lethal dose (30 Gy). A significant increase in the enzyme activity was registered 3 and 24 h following irradiation. Changes in nucleoside diphosphatkinase activity were more pronounced in mitochondria (particularly in liver mitochondria) than in the supernatant fraction.