Vanillic Acid Excretion during Stress

Abstract

RECENT reports of the metabolic conversion of the 3 : 4-dihydroxyphenyl into the 4-hydroxy-3-methoxyphenyl grouping^1,2 and of the occurrence in urine of 4-hydroxy-3-methoxymandelic acid³, a metabolite of adrenaline and noradrenaline, prompt us to record briefly our own findings along these lines. Aromatic compounds extracted by ether from acid-hydrolysed urine have been examined chromatographically by a method⁴ derived from that described by Boscott⁵; methylated products have been found to be invariably excreted by human subjects following oral administration of small doses (100–300 mgm.) of catechols. The compounds fed and metabolites detected are so similar to those described previously as to need little further comment; however, it has been observed, in one case at least, that methylation is not necessarily confined to the hydroxyl group in the 3-position, since 3-hydroxy-4-methoxycinnamic acid has been identified, together with the isomeric 4-hydroxy-3-methoxy compound, among the substances detected following administration of caffeic (3,4-dihydroxycinnamic) acid. Both these acids have been regularly detected in normal urines following acid hydrolysis.