Effect of Phenylalanine and Its Metabolites on the Brain Serotonin Level of the Rat.

Abstract

Wistar rats were placed on diets supplemented with 7% phenylalanine, 4.5% phenylpyruvic acid, 3% orthohydroxyphenylacetic acid or 4% phenylacetic acid. Analysis of brain samples for serotonin after several days on these diets showed that phenylalanine feeding effectively lowered brain serotonin, phenylpyruvic acid feeding did so less effectively, and phenylpyruvic acid and o-hydroxyphenyl-acetic acid feeding caused no significant change.