Metabolism of, and DNA methylation by, N-nitrosomethylbenzylamine in chicken.
The metabolism of 14C-nitrosomethylbenzylamine (NMBA) was studied in chicken. Following a single IV dose of 2 mg/kg, 14C-NMBA was cleared from the blood with a half-life of 3.8 min. At 10 min after administration 14C-NMBA was totally metabolized in the liver, whereas in the esophagus no measurable metabolic degradation had taken place. Maximum exhalation of radioactive CO2 occurred 1 h after IV administration of NMBA, and 11% of the total radioactivity had been exhaled as CO2 by 8 h. These results are compared with data on the metabolism of NMBA in the rat. The analysis of methylated bases in the DNA of different organs of chicken revealed that 7-me guanine was formed in all organs. The highest amount of 0(6)-me guanine was found in liver DNA, followed by kidney DNA. O6-me guanine was not detectable in any other organ. The O6-/7-me guanine ratio in DNA was calculated to be 0.05 and 0.02 for liver and 0.01 for kidneys.
D000818:Animals; D002645:Chickens; D004247:DNA / Q000378:metabolism*; D004128:Dimethylnitrosamine / Q000031:analogs & derivatives* / Q000378:metabolism; D004947:Esophagus / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D008745:Methylation; D008862:Microsomes, Liver / Q000378:metabolism
D004247:DNA; C014707:nitrosobenzylmethylamine; D004128:Dimethylnitrosamine