Effect of exogenous and endogenous nitrosation factors on formation of N-nitrosodimethylamine in rats depending on the status of purine catabolism

Nitrogen dioxide's rats' inhalations with injections per os of pyrazole, amidopyrine and sodium nitrite lead to considerable increasing of endogenic N-nitrosodimethylamine formation, which had been determined by system gas chromatograph-thermal energetic analyser. This increasing essentially didn't depend on the rats' immunisation by vaccine BCG, which leads to the intensification of NO synthesis by peritoneal macrophages and others manifestations of their metabolic activation: increasing of creatine kinase and adenosine desaminase activities. It hadn't been brought to light the obvious dependent between changes of xanthine oxidase and xanthine dehydrogenase activities in the liver and blood serum and intensification of lipids peroxidation and also the amount of N-nitrosodimethylamine in the rats in the conditions of endogenic and exogenic nitrosation factors' influence.     

Characteristics of action of precursors of carcinogenic nitroso-compounds on cell cultures

On the primary rat lung cell cultures, a study was made of the transforming action of sodium nitrite (NN) and amidopyrine combination with the control for formation of carcinogen--N-nitrosodimethylamine (NDMA) in growth medium. The manifestation of transformation was registered by appearance of morphological changes and multilayer growth foci. As criteria for evaluation after 48 hour treatments with NDMA, NN and AP, were used DNA-synthetizing activity of cells, mitotic index, frequency of mitoses pathology, monolayer density. The effects of transforming dose of NN alone and in combination with AP were the same. But malignization (tumor development in newborn rats in the points of cell suspension inoculation) took place only after administration of NN in combination with AP, when carcinogen was formed. Theophylline decreased the action of NN-AP combination.