A novel anti-ulcer agent (TEI-5103) acting directly on the gastric mucosa from lumen. II: Distribution of TEI-5103 to gastric mucosa in rats

Abstract

In the present study, we examined the distribution of TEI-5103 to gastric mucosa, as a target tissue, from the gastric lumen after oral administration of ¹⁴C-TEI-5103 to rats at its anti-ulcer dose (200 mg/kg).
When given orally, the radioactivity in gastric mucosa was much higher than that in plasma, unlike after intraduodenal administration. And the radioactivity in gastric mucosa was mostly present as unchanged drug, which was different from that in plasma. The concentration of unchanged drug in the gastric mucosa after oral administration was about 100 times higher than that after intraduodenal dosing. Additionally, radioactivity was observed in plasma after intragastric administration under pylorus ligation, indicating that TEI-5103 is at least absorbed from the gastric lumen.
In conclusion, we demonstrated TEI-5103 penatrated well to gastric mucosa as a target tissue directly from the gastric lumen after oral but not after systemic administration. These results suggest that TEI-5103 exerts its anti-ulcer effect by acting directly on the gastric mucosa when the drug is given orally.