Metabolism of 3-Methoxy-4-Hydroxyphenylalanine in Man

Abstract

Three-methoxy-4-hydroxyphenylpyruvic acid (MHPPA) was isolated and identified in urine from subjects receiving D,L-3-methoxy-4-hydroxyphenylalanine (MHPhe). The excretion was about 5 times higher when the amino acid was given intravenously than when it was given by mouth. About 25 per cent of the administered L-form of the MHPhe was excreted as MHPPA. Apart from MHPPA and the unchanged amino acid, mainly the D-form, the administration of D,L-MHPhe was not followed by any demonstrable increase in phenolic compounds in the urine.

Key Words:

• Amino acids
• hydroxylamines
• neoplasms
• nervous tissue