by using both a monoamine oxidase ( mao ) inhibitor ( pargyline ) and a serotonin precursor , 5-hydroxytryptophan rather than l-tryptophan , with or without an inhibitor of serotonin synthesis , p-chlorophenylalanine , we have demonstrated that many lc neurons have the capacity to accumulate serotonin and not other indoleamines .
C0000578
5-hydroxytryptophan
C0041249
l-tryptophan