L‐glutamate is an abundant dietary amino acid, which can be free or bound to other amino acids within proteins. It plays an essential role in transdeamination and gluconeogenesis, and becomes a substrate for the synthesis of the antioxidant glutathione and the polyglutamated folic acid. The intestine extracts most of the dietary glutamate where acts as the main fuel for nutrient absorption. However, glutamate metabolism in the gastric mucosa is poorly understood. Recently, we found that dietary supplementation with monosodium glutamate can ameliorate the inflammation and the atrophy of pepsinogen‐secreting chief cells and acid secreting parietal cells caused by chronic infection with Helicobacter pylori. To uncover the protective mechanism of glutamate, we isolated chief cells from rat stomach by counterflow elutriation and density gradient. When cells became confluent, we exposed them to either buffer or 20 mM glutamate for 2 h. The molecular profile between both treatments was compared by GeneChip analysis, which suggested that L‐glutamate may detoxify ammonia through the synthesis of glutamine and signal cells through glutamate receptors and glutamate transporters.