[Effect of amizon on structural modifications of liver nuclear chromatin from rats, intoxicated with tetrachloromethane].

The actions of the amizon on the antioxidant activity and free radicaloformation level in the nuclear chromatin fractions of rat liver methan tetrachlorid intoxication was studied using the Fe(+2)-induction biochemiluminescence and microcalorimetry methods. The amizon genomoprotective effect on the chromatin transcriptionally active fraction was shown.

[Antiradical and antioxidant properties of nonsteroidal anti-inflammatory agents--derivatives of pyridinecarboxylic acid].

A number of pyridincarboxylic acid derivatives PV-1-4, 7 and emoxypine preparation antioxidative activity in yolk lipoprotein suspension was studied by a method of Fe(2+)-initiated biochemiluminescence. Lipid peroxidation in suspension was effectively inhibited by the studied compounds in various concentration ranges. PV 1, 3, 4, 7 inhibited lipid peroxidation at the concentrations 100-fold, then those of PV 2 and emoxypine.

[Chromatin-protective action of the biologically active preparation BTK-8L in tetrachloromethane and chlorophos poisoning].

Results obtained from the study of the interaction between the phytosteroid preparation (BTK-8L) and fractionated rat liver nuclear chromatin under conditions of the tetrachloromethane and chlorophos intoxications are described. It is shown that preventive injection of BTK-8L to the animals has a partial protective effect on transcriptionally active and repressed liver chromatin. This preparation interacts with chromatin histone proteins binding with them and changes the nucleoprotein complex structure as a results of which the chromatin fraction components become less accessible to the damaging action of tetrachloromethane and chlorophos.

[Interaction of a substance based on phytoecdysteroids (BTK-8L) with components of fractionated chromatin from intact rat liver].

Results of the study of interaction of the phytoecdysteroid preparation (BTK-8L) with fractionated rat liver nuclear chromatin were described. It was shown that the interaction resulted in the "loosening" of the histone proteins structure both in active and repressed chromatin. At the same time the reparative DNA synthesis in the repressed fraction was stimulated.

[Genoprotective effect of drugs based on ecdysteroids in poisoning of rats with tetrachloromethane and chlorophos].

Molecular mechanisms of chromatin damage have been investigated during tetrachloromethane and chlorophos intoxication of experimental animals. Introduction of tetrachloromethane to experimental animals induced chromatin degradation causing a partial loss of histone H1-DNA fragmentation and formation of intermolecular bonds: DNA-protein. Intoxication with chlorophos results in repression of a part of genes due to augmented chromatin compactness.

[Mechanisms of the genoprotective action of a phytoecdysteroid drug (BTK-8L) in chromatin damage by chlorofos].

Genoprotective effect of preparation BTK-8L from plant steroids at prophylactic injection to experimental animals at chromatin damage by chlorofos was revealed. Antioxidant action of the preparation, being most highly expressed in the transcriptionally active chromatin fraction, is, probably, the most likely mechanism of the action. The realization of this action might be carried out as a result of the direct binding of BTK-8L with the chromatin protein-lipid complex, which was revealed during the analysis of the model systems showing binding of the preparation with chromatin fractions in vitro.

[Mechanisms of genoprotective action of a phytoecdysteroid drug(BTK-8L) in chromatin damage by tetrachloromethane].

Hepatoprotective action of prophylactic injection of aqueous solution of preparation BTK-8L from plant ecdysteroids to experimental animals with the liver damage by tetrachloromethane was revealed. This effect at least partially was connected with the genoprotective action of the given preparation. As a result, normalization of free radical chromatin lipid peroxidation reaction, modified at the intoxication, as well as partial correction of physical and chemical properties of chromatin protein-lipid complex were those molecular mechanisms of genoprotective action of BTK-8L, which were manifested by the influence of the preparation on such indices which characterized the depth structure of the complex as microviscosity and energy transfer from the protein to the lipid probe.

[Effect of cadmium chloride on DNA-, RNA-polymerase activity and lipid peroxidation of chromatin fraction in rat liver].

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.