[Effect of cadmium chloride on DNA-, RNA-polymerase activity and lipid peroxidation of chromatin fraction in rat liver]. / Vliianie khloristogo kadmiia na DNK-, RNK-polimeraznuiu aktivnost' i pereokislenie lipidov fraktsii khromatina pecheni krys.

Introduction of the cadmium chloride water solution to experimental animals induces changes in biochemical parameters which characterize structural and functional activity of transcriptionally active and repressed chromatin fractions. In the intoxicated chromatin-active fraction the DNA/protein ratio increases and DNA-polymerase alpha-activity decreases while in repressed chromatin activity of RNA polymerase I decreases as compared with controls. Change in intensity of lipoperoxidation reactions may underlie the cadmium chloride genotoxicity. This thesis is proved by an augmented level of NADPH-induced lipoperoxidation in active chromatin fraction.

[Biochemical characterization of fractionated rat liver chromatin in experimental D-hypovitaminosis and after administration of steroidal drugs]. / Biokhimicheskie kharakteristiki fraktsionirovannogo khromatina pecheni krys v usloviiakh éksperimental'nogo D-gipovitaminoza i pri vvedenii preparatov steroidov.

Marked changes in the structural and functional characteristics of liver nuclear chromatin fractions are observed under experimental D-hypovitaminosis, which differ in the degree of transcriptional activity. DNA-polymerase activity and activity of the fraction, enriched with RNA-polymerase I, increases in the active fraction. Free radical LPO reactions are modified in the chromatin fraction with low activity and to the less degree in the active one. Disturbances of chromatine structural properties are caused with the change in the protein and lipid components of chromatin. Administration of ecdysterone preparations (separately and together with vitamin D3) has a partial corrective effect on structural and functional organization of nuclear chromatine. At the action of ecdysterone normalization of LPO reactions modified by pathological changes is observed in the chromatin fraction with low activity and to the less degree in the active one. This kind of influence corrects to the less degree chromatin functional activity and quantitative and qualitative modifications of its protein component. Simultaneous influence of ecdysterone and vitamin D3 leads to the partial normalization of the biochemical indices studied (except for those which characterize LPO reactions) mainly in the active chromatin fraction.

[Changes in the structure and reactions of lipid peroxidation of liver chromatin as affected by 0,0-dimethyl-0,2,2-dichlorovinylphosphate]. / Izmeneniia struktury i reaktsii lipopereokisleniia khromatina pecheni pod vliianiem 0,0-dimetil-0,2,2-dikhlorovinilfosfata.

Intoxication of rats by 0,0-dimethyl-0-2,2-dichlorovinylphosphate (DDVPh) leads to marked biochemical changes of transcriptionally active (TACh) and repressed (RCh) liver chromatin fractions. These changes are connected with structural relaxation of the fractions, which is manifested by the increase of intensity of protein self-fluorescence. Free radical nature of these changes was supposed, which was proved by the modification of LPO reactions in the both chromatin fractions under the influence of the pesticide concerned.