Comparison of urinary nitrate, N-nitrosoproline, 7-methylguanine and 3-methyladenine levels in a human population at risk for gastric cancer.
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.
Stillwell
W G
WG
Division of Toxicology, Massachusetts Institute of Technology, Cambridge.
Xu
H X
HX
Glogowski
J
J
Wishnok
J S
JS
Tannenbaum
S R
SR
Correa
P
P
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
D009566:Nitrates; D009602:Nitrosamines; C025946:3-methyladenine; D006147:Guanine; C008450:7-methylguanine; C010259:nitrosoproline; D000225:Adenine