Chemical and Pharmaceutical Bulletin · 1978 · 16 citations · 0 references
PharmacyPharmacokineticsPharmacologyMass Spectrometric AnalysisPharmacodynamicsPharmacokinetic ModelingAmino Acid MetabolismDrug DispositionUrinary ExcretionArea Under The Plasma Concentration-time CurveConcentration-time Curve CharacterizationIsotope DilutionIsotope Dilution AnalysisIsotope Dilution Mass SpectrometryPlasma Concentration - Time ProfilePlasma Concentration-time AnalysisStable Isotope Dilution Analysis
By means of mass fragmentography using the isotope dilution method, the measurement of the plasma concentration of aminopyrine (AM) and its metabolites was performed successfully. It was clarified from the plasma concentration-time curve that the individual differences were observed in two processes which are demethylation of AM to 4-monomethylaminoantipyrine (MAA) or MAA to 4-aminoantipyrine (AA) and acetylation of AA to 4-acetylaminoantipyrine. Furthermore, a quantitative correlation between the plasma concentration and the amount of urinary excretion was discussed.