EFFECTS OF NC-1300-O-3 ON GASTRIC MUCUS SECRETION AND PROSTAGLANDIN RELEASE IN RATS

We investigated the effect of NC-1300-O-3 on gastric mucus secretion a nd prostaglandin release into the gastric lumen in rats. NC-1300-O-3 f ollowing single or repeated administration for up to 4 weeks significa ntly increased the hexose content in the gastric lumen at 10 to 100 mg /kg, p.o. Omeprazole and cimetidine at doses that strongly inhibited g astric acid secretion had no effect on the hexose content following si ngle or repeated administration for 8 days. When administered repeated ly for 8 days, NC-1300-O-3, omeprazole and cimetidine significantly de creased the hexosamine content in gastric surface mucosa, but signific antly increased gastric mucus secretion was observed at the same time only with NC-1300-O-3, indicating that this agent has a profile of act ion on gastric mucus metabolism different from those of omeprazole and cimetidine. NC-1300-O-3 at 10 and 30 mg/kg, p.o. and omeprazole at 30 mg/kg, p.o. increased the release of prostaglandins into the gastric lumen, and this was markedly inhibited by pretreatment with indomethac in, suggesting that these agents may enhance prostaglandin biosynthesi s in the gastric mucosa. From these results, it seems that the enhance ment of NC-1300-O-3 on gastric mucus secretion and prostaglandin biosy nthesis in the gastric mucosa contribute to the antiulcer effect of NC -1300-O-3.