[Production of nitric oxide metabolites during transplanted tumors growth with different metastatic potential].

The endogenous formation of metabolites of NO - nitrite (NI), nitrates (NA) and volatile nitrosamines in the body, tumor tissue and by abdominal cavity by macrophages for dynamics was investigated in mice F1(C57BlxCBA), Balb/c and BDF with subcutaneous transplanted tumors (Erlich carcinoma - EC and metastatic Lewis lung carcinoma - LLC). It was shown that growth of EC was accompanied by a statistically significant increase in the concentrations of NI and NA in tumor tissue to (7.3±4.67)'10-6 - (7.8±2.57)'10-5 (mol/kg) for the first three weeks and a sharp increase in urinary excretion of NI and NA. The maximum total concentration of NI and NA - (3.,6±0.46)'10-5 in tissue LLC was registered during the early stage of the tumor growth (7 days); it later declined, negatively correlating with the mass of the tumor. NI secretion by abdominal cavity macrophages demonstrated statistically significantly decrease at the stage of intensive growth LLC (14, 21 days). The tissue of EC contained varied concentration of cancerogenic N-nitrosodimethylamine and N-nitrosodiethylamine at all investigated time points. Thus, the ability of different gistogenesis tumor tissue to synthesize metabolites NO depended on time parameters and was more pronounced for EC, than LLC.

[Effect of sweet pepper, enriched with selenium, on the transplantable Ehrlich carcinoma in mice].

Effect of sweet pepper enriched and non-enriched with Se on Ehrlich carcinoma growth at Balb/c mice was investigated. 1000 mg/kg of both preparations of sweet pepper (per os administration for mice of 9 months age) inhibited an early stage of tumour growth on 42-62% and 37-65% respectively. No effect on tumour growth was registered for 4 months mice.

[Experimental study of the effect of sodium nitrate on the functional neutrophil and macrophage activity]. / Eksperimental'noe izuchenie funktsional'noi aktivnosti neitrofilov i makrofagov v usloviiakh vozdeistviia nitrita natriia.

The impact of sodium nitrite on functional activity of macrophages and neutrophiles of the abdominal cavity and blood of mice BALB/c was investigated in vitro and in vivo experiments. Functional activity was estimated according to formation of oxygen active forms. It was shown that sodium nitrite significantly inhibits formation of reactive oxygen species released from mouse peritoneal neutrophiles and macrophages, when they are being activated in vitro. Sodium nitrite was given in water at concentration 500.0 mg/l mice for 210 days immunodepression action was revealed which expressed reduction by leukopoes and decrease functional activity of blood neutrophils. Under the same conditions nitrite did not effect on functional activity of resident peritoneal macrophages.

[Effect of soybean isoflavones on antioxidant status in rats fed diet with oxidized linseed oil]. / Vliianie izoflavonov soi na antioksidantnyi status krys, poluchavshikh ratsion s okislennym l'nianym maslom.

The maintenance of male Wistar rats on semi-synthetic diets containing oxidized flaxseed oil for 4 weeks caused decrease in serum total antioxidant activity, significant suppression of microsomal UDP-glucuronosyl transferase activity and benzpyrene hydroxylase activity, increase in reduced glutathione level and catalase activity of liver. Supplementation of diets with 0.05% of soy isoflavones has resulted in normalization of investigated characteristics.

[Modifying effect of nitrites on pulmonary blastogenesis and viral leukogenesis in mice: role of nitric oxide and dioxide]. / Modifitsiruiushchee deistvie nitritov na legochnyi blastomogenez i virusnyi leikogenez u myshei: vozmozhnaia rol' okisi i dvuokisi azota.

The long-term effects of sodium nitrite (NaNO2) on carcinogenesis induced by urethane (total dose 1.0 mg/g body weight) in low-grade cancer F1 (C57BLxCBA) and high-grade A/Snell mice and on viral (Rausher leukemia virus) leukomogenesis in Balb/c mice. The murine intake of NaNO2 with water (50 mg/l) causes a statistically significant increase in the number of adenomas in the lung. Examining the mechanism of conversion of NO2- to NO led to the assumption that the free radical compounds NO and NO2 are involved in the potentiating action of NO2 on blastomogenesis. The use of the oxidant emoxypine (3-hydroxypyridine) confirmed the above. The role of NO and NO2 in the intracellular processes under the modifying effects of nitrites and nitrates on blastomogenesis is analyzed.

[Effects of selenium on endogenous synthesis of N-nitrosamines and toxicity of nitrites in rats]. / Vliianie selena na éndogennyi sintez N-nitrozaminov i toksicheskoe deistvienitritov u krys.

Male Wistar rats were fed selenium (0.2, 2.9 or 5.5 mg/kg of dry feed) in the form of selenomethionine. They also received for 6 weeks amidopyrine (33 mg/kg b.w.) and/or sodium nitrite (20 mg/kg b.w.) administered intragastrically. The quantitation of endogenously synthetized volatile nitrosamines in the stomach, selenium in the serum, biochemically evaluated nitrite and nitrosamines toxicity revealed an inverse relationship between feed selenium concentrations and the amount of endogenously produced nitrosodimethylamine from equal precursor doses. A protective selenium effect on methemoglobin-producing action of nitrite ions was established. It is shown that introduction of precursors induces increased body need in selenium.

[Food content of nitrates and nitrites and their daily intake]. / Soderzhanie v produktakh pitaniia nitratov i nitritov i otsenka ikh postupleniia s sutochnym ratsionom.

The studies performed by the authors show that 85-92% of nitrates and 53-60% of nitrites from the overall ration are taken with vegetables and meat products, respectively. An approximate daily supply of nitrates with food and water has been calculated for workers, employees and pensioners living in Moscow. The values obtained do not surpass the permissible daily dose of nitrates set up by the experts of the Carcinogenic Substances Committee at the Ministry of Health.