the effect of oral tyrosine or tryptophan ingestion on plasma concentrations of norepinephrine ( ne ) , dopamine ( da ) , epinephrine ( epi ) , and 3,4-dihydroxyphenylacetic acid ( dopac ) was investigated in a double blind , placebo-controlled study in fasted men .
C0028351
norepinephrine
C0014563
epinephrine