There are two responsible enzymes
in catabolism of catecholamines (CAs);
monoamine oxidase (MAO) and
catechol-o-methyl transferase (COMT).
MAO an iron- and a flavine- containing
enzyme is located in the outer
mitochondrial membrane and exhibited
in virtually all tissues of mammals
catalyzing the oxidative deamination of
monoamines (1,2).