Intragastric CO₂ and Nitric Oxide Participate in the Regulation of Peptoneinduced Gastrin Release in Humans

Abstract

Background: Moderate acidification of the gastric lumen inhibits peptone-induced gastrin release. The aim of the present study was to investigate if the gastric acid neutralization products CO₂ (from secreted HCO₃^-) and NO (from reduced salivary nitrite) could act as intermediate messengers between luminal acidity and the inhibition of peptone-induced gastrin release. Methods: Fourteen healthy volunteers (mean age, 27 years; range, 20-39 years; 3 women) participated in the study. Intragastric perfusion with saline or peptone was performed on the healthy volunteers. Venous blood samples were analyzed for serum gastrin concentrations. Intragastric NO was measured by chemiluminescence. Results: Basal serum gastrin ranged between 11 and 23 pmol/l. Peptone in Sörensen's phosphated buffer (pH 6.9, P_CO2

• Acid Bicarbonate Carbon Dioxide Gastric Gastrin Nitrate Nitric Oxide Nitrite Saliva Stomach