Figure 3: Sympathoneural sources of plasma levels of catechols.

Abbreviations: ALDH = aldehyde dehydrogenase; AR = aldehyde/aldose reductase; Cys-DA = 5-S-cysteinyldopamine; Cys-DOPA = 5-S-cysteinylDOPA; DA = dopamine; DBH = dopamine-beta-hydroxylase; DHPG = dihydroxyphenylglycol; DOPAC = dihydroxyphenylacetic acid; DOPAL = dihydroxyphenylacetaldehyde; DOPEGAL = dihydroxyphenylglycolaldehyde; LAAAD = L-aromatic-amino-acid decarboxylase; MAO = monoamine oxidase; NE = norepinephrine; NET = cell membrane norepinephrine transporter; TH = tyrosine hydroxylase; VMAT = vesicular monoamine transporter.