title: Lack of metabolism of 2,6-dimethyldinitrosopiperazine by microsomes and postmicrosomal supernatant prepared from the rat esophagus and non-glandular stomach.
abstract: Microsomes and postmicrosomal supernatant were prepared from the esophagus and non-grandular stomach of rats. Using these fractions, we could not demonstrate in vitro metabolism of 2,6-dimethyldinitrosopiperazine (DMDNP), a potent esophageal and non-grandular stomach carcinogen in rats. The esophageal and non-grandular stomach fractions did metabolize N-nitrosopyrrolidine (NPYR) to a small extent, and liver microsomes and postmicrosomal supernatant metabolized both nitrosamines to a similar extent. Therefore, we advise caution in the interpretation of metabolic studies using 'target' and 'non-target' organs as indicative of activation of compounds to proximate carcinogens.
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004947:Esophagus / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism*; D008297:Male; D008861:Microsomes / Q000378:metabolism*; D008862:Microsomes, Liver / Q000378:metabolism; D009242:N-Nitrosopyrrolidine / Q000378:metabolism; D009602:Nitrosamines / Q000032:analysis / Q000378:metabolism*; D010879:Piperazines / Q000032:analysis / Q000378:metabolism; D051381:Rats
chemical_list: D009602:Nitrosamines; D010879:Piperazines; C021111:2,6-dimethyldinitrosopiperazine; D009242:N-Nitrosopyrrolidine