Effects of anti-acid secretory agents on various types of gastric mucus

Total, acidic, and sulfated mucus contents in the gastric mucosa were evaluated after administration to rats of ranitidine and pirenzepine, antagonists of gastric parietal cell receptors; omeprazole, a proton-pump/inhibitor; and misoprostol, a prostaglandin E1 preparation. Total gastric mucus content was significantly decreased by ranitidine, but contents of acidic mucus and sulfated mucus showed a slight increase. Total mucus and acidic mucus contents were slightly increased after administration of pirenzepine, whereas the sulfated mucus content was significantly increased. The total gastric mucus content was significantly decreased after administration of omeprazole, but acidic mucus increased slightly and sulfated mucus increased significantly. All mucus contents were unchanged after administration of anti-acid secretory dose of midoptodyol. After administration of either ranitidine or omeprazole, the neutral mucus content decreased, but the total acid and sulfated mucus contents were not decreased. Changes in various mucus contents following inhibition of acid secretion are different for different drugs, and it was suggested that production of neutral mucus and secretion of acid mucus were reduced by strong inhibition of acid secretion.