sodium-nitrite and diethylamine

The inhibiting effect of organic Se (selen-enriched yeast Bioselen) on the endogenous synthesis of N-nitrosubstances was investigated in the Wistar rats, receiving 15 mg of sodium nitritis and 24 mg of diethylamin per 1 kg of bodyweight during 22 days. The level of nitrosoprolin synthesis and (NPro) and the level of nitrosodiethyl (NDie) in the stomach of rats served as the main indices. The highest level of NPro and NDie were revealed in the rats, without selen supplementation (581.2 +/- 113.3 mg per kg of bodyweight and 29.8 +/- 3.0 mg per kg of bodyweight). The highest inhibiting effect of Se was 54.5% for NPro and 54.7% for NDie and it was shown for the Se concentration of 1.5 mg per 1 kg of forage. The increase of Se dosage to 3.0 mg per 1 kg of forage was less effective and resulted in 25.5% of inhibiting of NPro u 47.0% - NDie.

Topics: Administration, Oral; Animals; Dietary Supplements; Diethylamines; Diethylnitrosamine; Dose-Response Relationship, Drug; Gastric Mucosa; Mutagens; Nitrosamines; Rats; Rats, Wistar; Selenium; Sodium Nitrite; Stomach

Separate or joint ingestions of water solutions of sodium nitrite and/or N-diethylamine by rats fed iron deficiency diet caused sharp increasing of N-nitrosodiethylamine level in stomach, a decreasing of Hb and increasing of MetHb concentrations in blood of animal. These effects were greater on iron deficient diet than on control diet. The nitrite ingestion caused a decline level of cytochrome P-450 and inhibition of lipid peroxidation in rat liver.

Topics: Animals; Cytochrome P-450 Enzyme System; Diethylamines; Diethylnitrosamine; Hemoglobins; Iron; Iron Deficiencies; Lipid Peroxidation; Liver; Male; Methemoglobin; Nitrites; Nitrosamines; Rats; Rats, Wistar; Sodium Nitrite; Stomach

The dose-response relationship of steady-state nitric oxide (NO) administration on renal vascular resistance in isolated rat kidneys (IPRK) perfused at constant pressure was investigated after inhibition of NO synthesis with NG-monomethyl-L-arginine (L-NMMA). To study the influence of biological thiols on renovascular NO effects, experiments were carried out with Krebs-Henseleit (KH) perfusate solutions alone, and in combination with bovine serum albumin (KH-ALB). Steady-state administration of NO by gassing the perfusate with 0 to 340 ppm NO led to graded decreases in renovascular tone. The minimal effective NO perfusate concentration in the absence of endogenous NO synthesis was about 6 to 8 nM, whereas a near-maximal effect was observed with approximately 200 nM. The presence of albumin reduced the speed of onset of renal vasodilation and the maximal effect at a given concentration of NO. After termination of NO administration, NO-induced vasodilation persisted in KH-ALB perfused kidneys for 30 min, whereas KH-perfused kidneys showed a rapid reconstriction. These findings suggest that the prolonged, potent renal vasodilation was caused by a reaction of bovine serum albumin (BSA) with oxides of nitrogen to form S-nitroso-BSA. Nitrosothiol levels in the KH-ALB perfusate were found to be proportional to the concentration of NO administered. The above-mentioned findings, confirmed in identical experiments with diethylamine NONOate, a novel NO-liberating substance, support the biological importance of S-nitrosothiols (RS-NO) in the action and metabolism of endothelium-derived relaxing factor (EDRF) in the IPRK.

Topics: Animals; Arginine; Diethylamines; Dose-Response Relationship, Drug; In Vitro Techniques; Kidney; Male; Nitric Oxide; Nitroso Compounds; omega-N-Methylarginine; Perfusion; Rats; Rats, Sprague-Dawley; Serum Albumin; Sodium Nitrite; Sulfhydryl Compounds; Vascular Resistance

The effect of chronic administration of 0.002% N-nitrosodiethylamine (DENA), 0.002% diethylamine (DEA) and 0.0005% sodium nitrite (SN) on the functional state of the xenobiotic metabolizing system in rat liver was investigated. Administration of DEA and DENA increased concentration of cytochromes P-450 and b5. SN did not affect the enzymes of the monooxygenase system. Coadministration of DEA and SN maximally increased the concentration of cytochrome P-450. It is not possible to explain the phenomenon of combined administration of SN and DEA by simple summation of the effects caused by them separately. The activity of microsomal glutathione S-transferase did not change when DEA and SN were given together, yet increased when they were administered separately. The maximum increase of the total activity of cytosol glutathione S-transferases was observed following DENA. In all four experimental groups a decrease of isoenzyme 5-5 activity was observed. Investigation of Se-independent glutathione peroxidase activity showed the multivariance of response of the glutathione S-transferase family to the compounds studied. The concentration of hepatic free SH-groups increased following administration of DENA and decreased dramatically when SN and DEA were coadministered. When they were given separately the concentration remained at control level.

Topics: Alkylating Agents; Animals; Cytochrome P-450 Enzyme System; Cytosol; Diethylamines; Diethylnitrosamine; Glutathione Transferase; In Vitro Techniques; Liver; Male; Microsomes, Liver; Rats; Sodium Nitrite; Xenobiotics