Biosynthesis of dopamine, norepinephrine and serotonin COoH c一NH2 C.,, 酪氨酸(a 色氨酸 Tryptophan ydroxyla H Coc COOH 9,y CHe-Ch i <decarboxy L S-HTP decarboxylase H C-C- NHe ①,y-@ s-hydr。x oparin Figure 4.18 nthesis of serotonin 4,13 Biosynthesis of the catecholamines.Biosynthesis of dopamine, norepinephrine and serotonin 酪氨酸 色氨酸