Various sodium salts, potassium salts, a calcium salt and an ammonium salt induced ornithine decarboxylase and stimulated DNA synthesis in rat stomach mucosa.

Studies were made on the possible tumor-promoting activities of various salts of food additives in the glandular stomach mucosa of F344 male rats after their administration by gastric intubation. Up to 100-fold increases in ornithine decarboxylase (ODC) activity in the pyloric mucosa of the stomach with maxima after 8 h were observed after administration of sodium acetate at doses of 3.68-13.6 mmol/kg body weight, sodium L-ascorbate at doses of 8.55-17.1 mmol/kg body weight, Na2CO3 at doses of 4.73-14.2 mmol/kg body weight, sodium L-glutamate at doses of 12.8-17.1 mmol/kg body weight, sodium sorbate at doses of 8.92-17.1 mmol/kg body weight and (NH4)2SO4 at doses of 7.56-20.1 mmol/kg body weight. Increases of up to 100-fold in ODC activity with maxima after 16 h were also observed after intubation of KCl at doses of 10.1-22.0 mmol/kg body weight, K2SO3 at doses of 2.84-8.45 mmol/kg body weight, K2S2O5 at doses of 2.25-6.75 mmol/kg body weight and CaCl2 at doses of 2.0-4.08 mmol/kg body weight. Sodium acetate at a dose of 11.0 mmol/kg body weight, KCl at a dose of 20.1 mmol/kg body weight, K2S2O5 at a dose of 5.40 mmol/kg body weight and CaCl2 at a dose of 3.4 mmol/kg body weight induced up to 10-fold increase in DNA synthesis in the pyloric mucosa of the stomach with maxima after 16-24 h. These results suggest that these salts of food additives may, like NaCl, have tumor-promoting activities in the pyloric mucosa of rat stomach.