title: Comparison of urinary nitrate, N-nitrosoproline, 7-methylguanine and 3-methyladenine levels in a human population at risk for gastric cancer.
abstract: We have measured the urinary excretion of nitrate, N-nitrosoproline, 3-methyladenine and 7-methylguanine in a human population at high risk for gastric cancer. A strong correlation was observed between nitrate and N-nitrosoproline excretion (p less than 0.00000); statistically significant correlations (p less than 0.05) were also observed for N-nitrosoproline with 3-methyladenine (p = 0.003) and with 7-methylguanine (p = 0.03) and for 7-methyl-guanine with nitrate (p = 0.02), although these correlations were sensitive to outliers. Smokers appeared to excrete slightly higher levels of 3-methyladenine than nonsmokers; no other difference was observed between smokers and nonsmokers or between drinkers and nondrinkers. The correlation between N-nitrosoproline excretion and nitrate excretion supports the hypothesis that elevated endogenous nitrate levels may contribute to elevated endogenous formation of N-nitroso compounds.
authors.affiliation: Division of Toxicology, Massachusetts Institute of Technology, Cambridge.
authors.forename: W G
authors.initials: WG
authors.lastname: Stillwell
authors.forename: H X
authors.initials: HX
authors.lastname: Xu
authors.forename: J
authors.initials: J
authors.lastname: Glogowski
authors.forename: J S
authors.initials: JS
authors.lastname: Wishnok
authors.forename: S R
authors.initials: SR
authors.lastname: Tannenbaum
authors.forename: P
authors.initials: P
authors.lastname: Correa
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000652:urine; D006147:Guanine / Q000031:analogs & derivatives* / Q000652:urine; D006801:Humans; D009566:Nitrates / Q000652:urine*; D009602:Nitrosamines / Q000652:urine*; D012306:Risk; D013274:Stomach Neoplasms / Q000209:etiology* / Q000652:urine
chemical_list: D009566:Nitrates; D009602:Nitrosamines; C025946:3-methyladenine; D006147:Guanine; C008450:7-methylguanine; C010259:nitrosoproline; D000225:Adenine