Combined effect of nitrosodimethylamine and aniline on the enzyme systems of subcelluar structures.

The authors studied combined effect of aniline (20 mg/kg for a period of 4 weeks in drinking water) and nitrosodimethylamine (NDMA) (30 mg/kg, a single intragastric dose) on the activity of enzymes of different subcellular structures: endoplasmic reticulum (cytochromes P450, B5, acetylesterase), mitochondria (malate dehydrogenase) and the content of N-acetylneuraminic acid in rat liver and of lysosomes (beta-glucuronidase, beta-galactosidase). The combined action of NDMA and aniline was accompanied by more pronounced changes in the indices under investigation than isolated administration of the given chemical substances. The most pronounced aggravation of the unfavourable changes was observed in the activity of enzymes connected with the processes of oxidation and energy supply to the cell (malate dehydrogenase) and the metabolism of glucuronides (beta-glucuronidase) as well as in the content of N-acetylneuraminic acid. This may be connected with the modifying effect of aniline on the toxic effect of NDMA.

The influence of tetrachloromethane on subcellular structures of rat hepatocyte lysosomal and cytoplasmic enzymes of the liver, lungs and blood serum of rats during continuous and intermittent action of tetrachloromethane.

The authors performed a comparative biochemical study of some enzymes of lysosomic origin (hyaluronidase, N-acetyl-beta-D-glucosaminidase, beta-glucosidase, beta-galatosidase and acid phosphatase), of the state of enzyme substrate system N-acetylneuraminic acid---aldolase of neuramic acid and of the activity of lactatedehydrogenase (soluble in cytosol and bound on mitochodria) in the liver, lungs and blood serum of rats at various regimens of the inhalation action of CCl4. On the basis of results obtained they determined the biological importance of the change of activity of enzymes differently localized in cells at the adaptation of an organisme to the noxious action of CCl4.