Immunomodulatory Effects Mediated by Dopamine

Figure 1

Metabolic pathways associated with DA. The metabolic pathways branching from the catabolism of L-phenylalanine are shown. (a) The dark blue arrows (over light yellow branches) indicate the DA generation pathway, and the red arrows (over light green branches) represent the noradrenaline and adrenaline pathway. Green arrows (over orange branches) show the alternative synthesis pathways to dopamine. The magenta arrows (over pink branches) show dopamine catabolism; the right side shows the normal pathways converging on HVA; the left side shows the catabolic pathways when dopamine concentrations are high in the cytoplasm. Many enzymes can transform dopamine and metabolites, such as COX enzymes (cyclooxygenases), producing dopaminochrome and dopamine quinone [44]. Other enzymes can produce sulfur and glucuronide derivatives. (b) The inset shows the most important products (circled with dotted lines) of metabolic pathways associated with DA. The compounds in these pathways are denoted by Kyoto Encyclopedia of Genes and Genomes (KEGG) code (http://www.genome.jp/kegg/). Enzymes with their classification codes (EC, http://www.chem.qmul.ac.uk/iubmb/enzyme/) and UNIPROT gene names are shown in squares.