[Nitrates and nitrites in gastric juice in chronic gastritis]

Atrophic gastritis is precancerous condition of the intestinal type of gastric carcinoma. This process supposes a genotoxic effect of N-nitroso-compounds which are formed in the stomach by nitrosation of nitrites and organic nitrogen compounds. The authors examined 41 patients with chronic superficial and atrophic gastritis. They examined the pH and concentration of nitrates and nitrites in gastric juice taken in the morning before meal. They discovered that in severe atrophic gastritis the amount of nitrates is significantly increased and the amount of nitrites is decreased, all in comparison with superficial gastritis. An exponential relation of the concentration of nitrites towards the pH of gastric juice was found to be NO2- = epH-6.5, CC = 0.935. A significant elevation of nitrite concentration was observed in cases of pH being higher than 5.5. Nitrate concentration altered in dependence of the value of gastric pH. Oral administration of 300 mg of vitamin C or 250 mg of vitamin E did not significantly affect the amount of gastric nitrites. The work discusses the mutual relation of nitrites, ascorbic acid and alpha-tocopherol towards the formation of N-nitroso-compounds in the stomach inflicted by atrophic gastritis. (Tab. 3, Fig. 2, Ref. 25.)