Enhanced lipid peroxidation in rat gastric mucosa caused by NaCl

The effects of NaCl on lipid peroxidation levels in gastric mucosa and urine were investigated in male Wistar rats. The animals were fed NaCl-supplemented diet at concentrations of 4.0, 2.0, 1.0, 0.5, 0.25 and 0% (control) for 5 weeks. Further groups were maintained on the 4.0 or 0% NaCl diets and simultaneously administered 20 p.p.m. indomethacin dissolved in the drinking water. When the rats were killed, a dose-related increase of malondialdehyde (MDA) was found in both gastric mucosa and urine, the urinary MDA levels clearly correlating with those for stomach tissue. Cell proliferation of fundic mucosa was also significantly increased in rats fed 4.0 or 2.0% NaCl-supplemented diet. Indomethacin suppressed the 4% NaCl-associated MDA increase in both gastric mucosa and urine as well as the elevation in cell proliferation. The results clearly show that administration of NaCl, a gastric tumor promoter, is associated with enhanced lipid peroxidation in the gastric mucosa.