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. 1987 Feb;28(2):216–220. doi: 10.1136/gut.28.2.216

Urinary N-nitrosoproline excretion: a further evaluation of the nitrosamine hypothesis of gastric carcinogenesis in precancerous conditions.

C N Hall, J S Kirkham, T C Northfield
PMCID: PMC1432965  PMID: 3557192

Abstract

Measurement of N-nitroso compounds in gastric juice by different methods has given conflicting results. In order to resolve this controversy, we have assessed endogenous nitrosation by the independent N-nitrosoproline excretion test in subjects who had previously undergone gastric juice analysis by one of these methods. Ten Polya gastrectomy, 10 pernicious anaemia and nine matched control subjects were fed 380 mg of nitrate in beetroot juice and 500 mg proline. N-nitrosoproline (N-Pro) synthesised intragastrically from these precursors, and quantitatively excreted by the kidneys, was measured in 24 hour urine samples (collection checked by creatinine clearance). N-Pro excretion (mean +/- SEM) was reduced (p less than 0.01) in pernicious anaemia (1.1 +/- 0.8 ng/day) compared with matched control (18.0 +/- 7.2 ng/day), and also tended to be lower (NS) in polya gastrectomy (3.2 +/- 2.3 ng/day). Twenty four hour intragastric pH was monitored on a separate occasion in 23 of the 29 subjects; 13 were hypoacidic (pH greater than 4 greater than 50% of 24 hours) and 10 were acidic. N-Pro yields were reduced (p less than 0.01) in the hypoacidic group (0.9 +/- 0.6 ng/day) compared with the acidic group (17.9 +/- 6.6 ng/day), and N-Pro was negatively associated with mean intragastric pH (tau = -0.53, p = 0.001). We conclude that endogenous synthesis of this specific N-nitroso compound is favoured by low rather than high pH. These results are concordant with those previously reported in gastric juice from the same subjects and suggest that nitrosation is chemically rather than bacterially mediated, contrary to the nitrosamine hypothesis of gastric carcinogenesis.

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Selected References

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  1. Correa P., Haenszel W., Cuello C., Tannenbaum S., Archer M. A model for gastric cancer epidemiology. Lancet. 1975 Jul 12;2(7924):58–60. doi: 10.1016/s0140-6736(75)90498-5. [DOI] [PubMed] [Google Scholar]
  2. Hall C. N., Darkin D., Brimblecombe R., Cook A. J., Kirkham J. S., Northfield T. C. Evaluation of the nitrosamine hypothesis of gastric carcinogenesis in precancerous conditions. Gut. 1986 May;27(5):491–498. doi: 10.1136/gut.27.5.491. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Keighley M. R., Youngs D., Poxon V., Morris D., Muscroft T. J., Burdon D. W., Barnard J., Bavin P. M., Brimblecombe R. W., Darkin D. W. Intragastric N-nitrosation is unlikely to be responsible for gastric carcinoma developing after operations for duodenal ulcer. Gut. 1984 Mar;25(3):238–245. doi: 10.1136/gut.25.3.238. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Lane R. P., Bailey M. E. The effect of pH on dimethylnitrosamine formation in human gastric juice. Food Cosmet Toxicol. 1973 Oct;11(5):851–854. doi: 10.1016/0015-6264(73)90144-2. [DOI] [PubMed] [Google Scholar]
  5. Milton-Thompson G. J., Lightfoot N. F., Ahmet Z., Hunt R. H., Barnard J., Bavin P. M., Brimblecombe R. W., Darkin D. W., Moore P. J., Viney N. Intragastric acidity, bacteria, nitrite, and N-nitroso compounds before, during, and after cimetidine treatment. Lancet. 1982 May 15;1(8281):1091–1095. doi: 10.1016/s0140-6736(82)92277-2. [DOI] [PubMed] [Google Scholar]
  6. Mirvish S. S., Sams J., Fan T. Y., Tannenbaum S. R. Kinetics of nitrosation of the amino acids proline, hydroxyproline, and sarcosine. J Natl Cancer Inst. 1973 Dec;51(6):1833–1839. doi: 10.1093/jnci/51.6.1833. [DOI] [PubMed] [Google Scholar]
  7. Ohshima H., Bartsch H. Quantitative estimation of endogenous nitrosation in humans by monitoring N-nitrosoproline excreted in the urine. Cancer Res. 1981 Sep;41(9 Pt 1):3658–3662. [PubMed] [Google Scholar]
  8. Reed P. I., Haines K., Smith P. L., Walters C. L., House F. R. Intragastric acidity, bacteria, nitrite, and N-nitroso compounds before, during, and after cimetidine treatment. Lancet. 1982 Jul 3;2(8288):39–39. doi: 10.1016/s0140-6736(82)91167-9. [DOI] [PubMed] [Google Scholar]
  9. Reed P. I., Smith P. L., Haines K., House F. R., Walters C. L. Gastric juice N-nitrosamines in health and gastroduodenal disease. Lancet. 1981 Sep 12;2(8246):550–552. doi: 10.1016/s0140-6736(81)90939-9. [DOI] [PubMed] [Google Scholar]
  10. Ruddell W. S., Bone E. S., Hill M. J., Walters C. L. Pathogenesis of gastric cancer in pernicious anaemia. Lancet. 1978 Mar 11;1(8063):521–523. doi: 10.1016/s0140-6736(78)90550-0. [DOI] [PubMed] [Google Scholar]
  11. Ruddell W. S., Walters C. L. Nitrite and N-nitroso compounds in gastric juice. Lancet. 1980 May 31;1(8179):1187–1187. doi: 10.1016/s0140-6736(80)91641-4. [DOI] [PubMed] [Google Scholar]
  12. Stockbrugger R. W., Cotton P. B., Eugenides N., Bartholomew B. A., Hill M. J., Walters C. L. Intragastric nitrites, nitrosamines, and bacterial overgrowth during cimetidine treatment. Gut. 1982 Dec;23(12):1048–1054. doi: 10.1136/gut.23.12.1048. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Sturniolo G., Carditello A., Bonavita G., Bartolotta M., Saitta E. Risk factors for development of primary cancer in the gastric stump. Intragastric nitrites and nitroso-compounds after surgery for duodenal ulcer. Acta Chir Scand. 1983;149(6):591–596. [PubMed] [Google Scholar]
  14. Tannenbaum S. R., Archer M. C., Wishnok J. S., Bishop W. W. Nitrosamine formation in human saliva. J Natl Cancer Inst. 1978 Feb;60(2):251–253. doi: 10.1093/jnci/60.2.251. [DOI] [PubMed] [Google Scholar]

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