Gastrointestinal Absorption of a New Reversible Proton Pump Inhibitor, YJA-20379-8, and its Pharmacokinetics after Oral Administration in Acetic Acid-induced Gastric Ulcer in Rats

Abstract

Abstract The absorption of YJA-20379-8 (3-butyryl-4-[5-(R)-(+)-methylbenzylamino]-8-ethoxy-1,7-naphthyridine) from various rat gastrointestinal segments was evaluated using in-situclosed-loops. The pharmacokinetics of the drug were also evaluated after oral administration to rats with acetic acid-induced gastric ulcer (AIURs). The concentrations of YJA-20379-8 in the biological samples were analyzed by HPLC. The absorption of YJA-20379-8 from stomach and jejunum was fast, but approximately 50% of the drug was recovered from each segment at 24 h. The total areas under the plasma concentration-time curves from time zero to 24 h (AUC0-24h) were 161, 392, 233, 365, and 226 μg min mL−1 for stomach, duodenum, jejunum, ileum, and colon, respectively. After oral administration of the drug, the plasma concentrations and the resultant AUC0-12h were not significantly different between control and AIURs. The detection limits of YJA-20379-8 in human plasma and urine were 50 and 100ng mL−1, respectively. The results suggest that modification of the oral dose of YJA-20379-8 may not be required in gastric ulcer patients if the present rat pharmacokinetic data could be extrapolated to man.