title: Gut reactions of radioactive nitrite after intratracheal administration in mice.
abstract: Intratracheal administration to mice of radioactive nitrite labeled with nitrogen-13 (13NO2-) (half-life, 9.96 minutes) in dosages that do not cause pharmacological perturbation reveals that oxidative and reductive reactions occur in different organs. Oxidation of 13NO2- to radioactive nitrate (13NO3-) predominates in the blood and liver. Reduction of 13NO2- occurs in those mice that harbor intestinal microflora; this reduction does not occur in germ-free mice. The intestinal reduction products include ammonium, glutamate, glutamine, and urea. With a detection limit of about 0.01 percent of the instilled nitrogen-13, no labeled nitrosamines were detected within 30 minutes. Reduced nitrogen-13 is transported out of the intensive into the circulatory system and appears in the urine along with 13NO3-. The biological half-period for 13NO2- destruction is about 7 minutes, and both oxidation and reduction products are formed.
mesh_terms: D000818:Animals; D006207:Half-Life; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000382:microbiology; D007442:Intubation, Intratracheal; D051379:Mice; D008807:Mice, Inbred BALB C; D009573:Nitrites / Q000008:administration & dosage / Q000378:metabolism*; D009590:Nitrogen Radioisotopes; D010084:Oxidation-Reduction; D013047:Specific Pathogen-Free Organisms; D014018:Tissue Distribution
chemical_list: D009573:Nitrites; D009590:Nitrogen Radioisotopes