At the beginning of this reaction, 1 molecule of 'Oxygen', 1 molecule of 'H2O', and 1 molecule of '5-Hydroxytryptamine' are present. At the end of this reaction, 1 molecule of 'NH3', 1 molecule of '5-Hydroxyindoleacetaldehyde', and 1 molecule of 'H2O2' are present.<br><br> This reaction takes place in the 'mitochondrial outer membrane' and is mediated by the 'amine oxidase activity' of 'MAOA-FAD complex'.<br>