Nicotine inhibits the metabolic activation of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in rats
- 1 May 1994
- journal article
- research article
- Published by Oxford University Press (OUP) in Carcinogenesis: Integrative Cancer Research
- Vol. 15 (5) , 1061-1064
- https://doi.org/10.1093/carcin/15.5.1061
Abstract
The effect of nicotine on the metabolism of the tobacco-specific nitrosamine 4-(methylnitrosamlno)-1-(3-pyridyl)-1-butanone (NNK) was studied in rats. [1-14C]NNK was s.c. injected at a dose of 0.08 μmol/kg. Co-administration of a 500-fold higher dose of nicotine (40 μmol/kg did not reduce the overall urinary excretion of radioactivity. However, the metabolic pattern in 24 h urine was significantly changed. Metabolites resulting from NNK activation by α-hydroxylatlon were significantly (P < 0.001) reduced to 72% of the control. Detoxification to N-oxides and the glucuronide of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol increased to 155% (P < 0.01) and 188% (P < 0.01) of the control respectively. These results suggest that nicotine, which occurs In concentrations up to 30 000-fold higher than NNK In mainstream smoke of cigarettes may have a protective effect against metabolic activation of NNK.Keywords
This publication has 0 references indexed in Scilit: