[Monoamine oxidase activity in gastrointestinal tract tissues of animals after irradiation and administration of pyridoxal phosphate].

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].

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.

[Catabolism of pyrimidine nucleotides in the liver of irradiated animals].

A study was made of the activity of nucleoside diphosphatase (NDPase, EC 3.6.1.

[Role of adenylate kinase, AMP deaminase and 5'-nucleotidase in the metabolism of adenylic nucleotides].

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.

[Adenylate kinase isoenzymes in rat liver and blood serum in radiation sickness].

A study was made of isoenzyme activity of adenylate kinase of rat liver and blood serum 3, 7 and 15 days following whole-body X-irradiation in a dose of 154.8 mC/kg. A considerable increase was noted in activity of isoenzyme II in mitochondria, and isoenzyme I in the liver supernatant fraction.

[5-nucleotidase activity in rat leukocytes, erythrocytes and blood serum during radiation sickness].

A study of 5-nucleotidase activity in the formed elements and blood serum of rats 1, 3, 7, 15 and 30 days after X-irradiation has demonstrated that it was increased in leukocytes at early times and inhibited at later times of the development of radiation sickness. In erythrocytes, inhibition of 5-nucleotidase activity was most pronounced on the 3d day. In blood serum, the enzyme activity was virtually invariable.

[Adenylate kinase activity of the blood of irradiated rats].

The direct and reverse adenylate kinase reactions were studied in blood of rats 1, 3, 7, 15 and 30 days after total X-ray irradiation with a dose of 154.8 mC/kg (600 R) dose. It is found out that adenylate kinase (CE 2.