Pharmacokinetics and biotransformation of beraprost sodium. IV. Metabolism of beraprost sodium in rat.

After oral administration of 3H-beraprost sodium to male rats at a dose of 1.0mg/kg, metabolites in urine and feces were analyzed by HPLC, and the structures of nine metabolites were determined by NMR spectroscopy, mass spectrometry and comparative HPLC with synthetic standards.The structures of the metabolites suggest metabolic pathway of beraprost sodium involving β-oxidation, oxidation of hydroxyl group at C15-position, hydrogenation of double bond and oxygenation at ω-side chain. Major metabolite in urine and feces was 2, 3-dinor-beraprost, a product of β-oxidation of beraprost sodium (11.26% of the dose in urine and 43.21% of the dose in feces).