[Effect of low-intensity 900 MHz frequency electromagnetic radiation on rat liver and blood serum enzyme activities].

The comparative analysis of the rat liver and blood serum creatine kinase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and purine nucleoside phosphorylase post-radiation activity levels after a total two-hour long single and fractional exposure of the animals to low-intensity 900 MHz frequency electromagnetic field showed that the most sensitive enzymes to the both schedules of radiation are the liver creatine kinase, as well as the blood serum creatine kinase and alkaline phosphatase. According to the comparative analysis of the dynamics of changes in the activity level of the liver and blood serum creatine kinase, alanine aminotransferase, aspartate aminotransferase and purine nucleoside phosphorylase, both single and fractional radiation schedules do not affect the permeability of a hepatocyte cell membrane, but rather cause changes in their energetic metabolism. The correlation analysis of the post-radiation activity level changes of the investigated enzymes did not reveal a clear relationship between them.

[Influence of ionizing radiation on enzymatic activity and state of nucleus-nucleolar apparatus in rat hepatocytes].

The effects of a single exposure of rats to the whole-body roentgen irradiation at the doses of 3.5 Gy and 4.5 Gy on the activity of creatine kinase, purine nucleoside phosphorylase, alanine aminotransferase, aspartate aminotransferase, as well as on the state of the nuclear-nucleolar apparatus in rat hepatocytes on the 6th and 13th days after radiation exposure have been studied.

[Purine nucleoside phosphorylase inhibitors and their clinical significance].

PNP catalyzes a reversible phosphorolysis of purine deoxy- and ribonucleosides with formation of (d)Rib-1-P and appropriate bases. PNP plays a leading role in the cell metabolism of nucleosides and nucleotides, as well as in maintaining the immune status of an organism. The major purpose of the majority of studies on the PNP is the detection of high-performance enzyme inhibitors, derivatives of the purine nucleosides, which are used in medicine as immunosuppressors.

[Role of individual phospholipids in the functional activity of human myocardial creatine kinase].

Regulating effect of individual phospholipids on the activity of creatine kinase MM from human myocardium was studied. Cardiolipin, phosphatidic acid, phosphatidyl serine and phosphatidyl choline (dipalmitoyl) stimulated the enzymatic activity, while phosphatidyl inositol and lysophosphatidyl choline inhibited the creatine kinase MM activity by 80-100%. When mechanisms of the phospholipids inhibitory effects were studied, mixed type of inhibition was detected in the presence of phosphatidyl inositol and non-competitive type--in presence of lysophosphatidyl choline if guanidine was used as a substrate.

[Purification and various properties of creatine kinase MM isoenzyme from the human heart muscle].

Homogeneous preparation of creatine kinase MM isoenzyme was isolated from human heart muscle using affinity chromatography on Sepharose containing immobilized Cibachron blue F3G-A. The enzyme was active at a wide range of pH 5.0-8.