Abstract

Isolated perfused kidneys of rats were used to determined renal metabolism of meperidine and its relation to meperidine excretion. Starting perfusate concentrations of meperidine were 18.4 and 190 micrograms/ml, and resulted in respective nonsaturation and saturation kinetics for removal of meperidine. Disposition of 14C-meperidine was followed and supplemented with measurements of meperidine by gas chromatography. A major renal metabolite was shown to facilitate the renal excretion of meperidine. This metabolite was identified by gas chromatography/mass spectrometry as the N-oxide of meperidine.