tryptophan ( 0.02-0.5 microm ) and 5-htp ( 0.02-0.2 microm ) caused variable and usually slight , but long-lasting , vascular responses or no vascular response a large dose of tryptamine ( 0.5 microm ) evoked variable vascular effects , while the same dose of 5-ht and 5-htp evoked marked and prolonged depressor effects .
C0041249
tryptophan
C0000578
5-htp