ABSTRACT
The activity of 5-nucleotidase (EC 3.1.3.5) and guanylate kinase (EC 2.7.4.8) in the mitochondria and supernatant of the brain and liver was determined in experiments on Wistar male rats 1, 3, 6, 24 and 48 h after the single total irradiation by gamma-quanta in a dose of 30 Gy. It is established that the activity of 5-nucleotidase in the liver endures phase changes with the predominance of the enzyme activation; in the brain it is higher during the whole period of investigation. The guanylate kinase activity lowers in the both fractions of the organs under study during the whole period of the experiment.
Subject(s)
5'-Nucleotidase/metabolism , Brain/enzymology , Liver/enzymology , Nucleoside-Phosphate Kinase/antagonists & inhibitors , Phosphotransferases/antagonists & inhibitors , Radiation Injuries, Experimental/enzymology , Animals , Brain/radiation effects , Enzyme Activation , Guanylate Kinases , Liver/radiation effects , Rats , Rats, Inbred Strains , Time FactorsABSTRACT
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.
Subject(s)
Gastric Mucosa/enzymology , Intestinal Mucosa/enzymology , Monoamine Oxidase/metabolism , Pyridoxal Phosphate/pharmacology , Radiation Injuries, Experimental/enzymology , Animals , Gastric Mucosa/radiation effects , Intestinal Mucosa/radiation effects , Male , Mitochondria/enzymology , Mitochondria/radiation effects , Oxidation-Reduction , Pyridoxal Phosphate/therapeutic use , Rabbits , Radiation Injuries, Experimental/drug therapy , Serotonin/metabolismABSTRACT
A state of the gamma-aminobutyric acid (GABA) system (glutamate, glutamate decarboxylase, GABA, GABA-alpha-ketoglutarate aminotransferase) and the coupled reactions (alpha-ketoglutarate dehydrogenase complex, aspartate- and alanine aminotransferases) was studied in three brain structures (cerebellum, brain cortex and truncus cerebri) after multiple administration of pyridoxal-5'-phosphate (PALP) and its Shiff base with GABA (5 injections at doses 10.0 and 15.0 mg/kg of body mass, respectively). Non-coenzymatic effects of PALP were found to prevail within 1 hr after its last administration: inhibition of PALP-dependent aminotransferases and activation of the alpha-keto-glutarate oxidative decarboxylation were observed. The opposite effects were detected after addition of PALP to brain homogenates in vitro. Administration of the PALP-GABA complex exhibited qualitatively similar to those of PALP effects on the reactions studied in brain. The data obtained suggest that parenteral administration of the coenzyme preparation caused a number of metabolic effects, which are sometimes far from unambigously predicted theoretical considerations. The similarity of PALP and PALP-GABA effects appears to demonstrate ready biotransformation of the Shiff base with liberation of PALP and GABA.
Subject(s)
Brain/drug effects , Pyridoxal Phosphate/pharmacology , gamma-Aminobutyric Acid/metabolism , Animals , Brain/enzymology , Brain/metabolism , Glutamate Decarboxylase/metabolism , Glutamate Synthase/metabolism , Injections, Intraperitoneal , Male , Pyridoxal Phosphate/administration & dosage , Rats , Rats, Inbred Strains , Schiff Bases/administration & dosage , Schiff Bases/pharmacology , gamma-Aminobutyric Acid/administration & dosageABSTRACT
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.
Subject(s)
Liver/metabolism , Pyrimidine Nucleotides/metabolism , Radiation Injuries, Experimental/metabolism , Animals , Cytidine Diphosphate/metabolism , Cytidine Monophosphate/metabolism , Cytidine Triphosphate/metabolism , Liver/radiation effects , Male , Rats , Rats, Inbred Strains , Uridine Diphosphate/metabolism , Uridine Monophosphate/metabolism , Uridine Triphosphate/metabolismABSTRACT
It is shown that gamma-irradiation of albino rats with a dose of 30 Gy leads to pronounced phase changes in monoaminoxidase activity and serotonin content in rat brain at early times after whole-body exposure. There is a similar direction of changes in the activity of the enzyme and in the content of the substrate adequate to the latter.
Subject(s)
Brain/metabolism , Mitochondria/enzymology , Monoamine Oxidase/metabolism , Radiation Injuries, Experimental/metabolism , Serotonin/metabolism , Animals , Cobalt Radioisotopes , Gamma Rays , Male , Rats , Rats, Inbred StrainsABSTRACT
A single total-body exposure of rats to gamma-rays in an absolutely lethal dose caused significant changes in the activity of fructosodiphosphate aldolase (ALD) and glucose-6-phosphate dehydrogenase (G-6-PDH) in the brain, liver, myocardium and skeletal muscles. The activity of ALD was mainly inhibited and that of G-6-PDH increased. Thus, the initial step of glycolysis was significantly inhibited and the key reaction of the pentose phosphate pathway enhanced in the irradiated body.
Subject(s)
Fructose-Bisphosphate Aldolase/metabolism , Glucosephosphate Dehydrogenase/metabolism , Radiation Injuries, Experimental/enzymology , Animals , Dose-Response Relationship, Radiation , Fructose-Bisphosphate Aldolase/radiation effects , Gamma Rays , Glucosephosphate Dehydrogenase/radiation effects , Glycolysis/radiation effects , Male , NADP , Radiation Injuries, Experimental/metabolism , Rats , Rats, Inbred Strains , Time Factors , Tissue DistributionABSTRACT
A whole-body X-irradiation (5.82 Gy) increases the activity of ornithine carbamoyl transferase (OCT) on days 3, 7, 15 and 60. After the administration of a complex of vitamins and coenzymes on days 7, 15 and 60 OCT activity decreased as compared to that of untreated animals. A correlation was noted between the activity of OCT in the liver and blood serum.
Subject(s)
Coenzymes/therapeutic use , Ornithine Carbamoyltransferase/metabolism , Radiation Injuries, Experimental/enzymology , Vitamins/therapeutic use , Animals , Radiation Injuries, Experimental/drug therapy , Rats , Rats, Inbred StrainsABSTRACT
The activities of adenylate kinase, AMP-deaminase and 5'-nucleotidase in various tissues of the rat were studied. The activity of the forward adenylate kinase reaction (ATP + AMP----2 ADP) against the back one (2 ADP----ATP + AMP) was predominant. The liver was shown to contain two, while the blood serum--three adenylate kinase isoenzymes. In the skeletal muscles, the catabolism of adenylic acid involving AMP-deaminase and 5'-nucleotidase predominantly occurred via deamination, in the liver--via dephosphorylation, while in the leucocytes, erythrocytes and blood serum the activity of these processes was essentially the same. In vitro, ATP enhanced the activity of AMP-deaminase in the liver, leucocytes and erythrocytes and decreased it in the blood serum. Under effects of ATP, the activity of 5'-nucleotidase in the leucocytes and blood serum was markedly elevated, that in the liver and erythrocytes was unaffected.
Subject(s)
AMP Deaminase/metabolism , Adenine Nucleotides/metabolism , Adenylate Kinase/metabolism , Isoenzymes/metabolism , Nucleotidases/metabolism , Nucleotide Deaminases/metabolism , Phosphotransferases/metabolism , 5'-Nucleotidase , AMP Deaminase/blood , Adenine Nucleotides/blood , Adenylate Kinase/blood , Animals , In Vitro Techniques , Isoenzymes/blood , Liver/enzymology , Male , Muscles/enzymology , Nucleotidases/blood , Rats , Rats, Inbred Strains , Tissue DistributionABSTRACT
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.
Subject(s)
Brain/enzymology , Liver/enzymology , Nucleoside-Diphosphate Kinase/radiation effects , Nucleoside-Phosphate Kinase/radiation effects , Phosphotransferases/radiation effects , Radiation Injuries, Experimental/enzymology , Animals , Gamma Rays , Male , Rats , Rats, Inbred Strains , Time Factors , Whole-Body IrradiationABSTRACT
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.
Subject(s)
Brain/enzymology , Liver/enzymology , Nucleoside-Diphosphate Kinase/metabolism , Phosphotransferases/metabolism , Radiation Injuries, Experimental/enzymology , Animals , Male , Mitochondria/enzymology , Mitochondria, Liver/enzymology , Radiation Injuries, Experimental/mortality , Rats , Rats, Inbred Strains , Time FactorsSubject(s)
Central Nervous System/radiation effects , gamma-Aminobutyric Acid/metabolism , 4-Aminobutyrate Transaminase/metabolism , Animals , Central Nervous System/metabolism , Female , Glutamate Decarboxylase/metabolism , Glutamates/metabolism , Male , Rabbits , Time Factors , Whole-Body IrradiationABSTRACT
The paper deals with changes in the activity of transaldolase in tissues of the liver, spleen and bone marrow of rats 4.24 h and on the 3 d, 7th, 18th, 30th, 45th, and 60th day after total X-ray irradiation in a dose of 600 R. The ionizing irradiation causes a stable inhibition of the enzyme activity in All tissues. The observed changes are homogeneous in their direction but have their own peculiarities for each tissue. Differences in the degree and extent of the enzyme activity changes at various stages of the X-ray lesion development in the tissues under study may be explained by their different sensitivity to the penetrating radiation.