5-Hydroxytryptophol: a metabolite of 5-hydroxytryptamine in rats

Abstract

The metabolism of 1''-N-acetyl-5-hydroxytryptamine and 5-hydroxytryptophol in rat-liver slices was studied. The former compound remained mainly unchanged (80-90%), whereas 60-70% of 5-hydroxytryptophol was metabolized, being partly oxidized to 5-hydroxy-indolylacetic acid and partly conjugated. l''-N-Acetyl-5-hydroxy-tryptamine and 5-hydroxytryptophol were chromatographically in-distinguishable but only the latter was shown to be a metabolite of 5-hydroxytryptamine. A scheme for the metabolism of 5-hydroxytryptamine is suggested. A major metabolite of 5-hydroxytryptamine excreted in rat urine is a 5-hydroxytryptophol-O-glucuronide. The chemical synthesis of 5-hydroxytryptophol is described.