the hydroxylation of tryptophan has been studied by measuring the accumulation of 5-hydroxytryptophan ( 5-htp ) and the concentrations of 5-hydroxytryptamine ( 5-ht ) and 5-hydroxyindoleacetic acid ( 5-hiaa ) in brainstem , frontal cortex and hypothalamus after inhibition of l-amino acid decarboxylase with benserazide hydrochloride and administration of either the vehicle or triamterene .
C0041249
tryptophan
C0000578
5-htp