Monoamine Oxidase Substrate Pool (None)

The "monoamine oxidase substrate pool" refers to the collection of endogenous monoamines—primarily noradrenaline (norepinephrine), other catecholamines (such as dopamine), and serotonin—that serve as substrates for the enzyme monoamine oxidase (MAO). MAO exists in two isoforms, MAO-A and MAO-B, both of which are mitochondrial flavoenzymes responsible for catalyzing the oxidative deamination of these neurotransmitters. By degrading neurotransmitters such as noradrenaline, dopamine, and serotonin in neural tissues—and also acting on dietary amines systemically—MAOs regulate synaptic levels of these signaling molecules. This regulation is crucial for mood balance, cardiovascular function, stress response, cognition, and more. The availability—and physiological effects—of these biogenic amines are directly regulated by this enzymatic pathway through either natural turnover or pharmacological manipulation.

Levels of noradrenaline/catecholamines/serotonin decrease or increase depending on MAO activity or inhibition, impacting neuropsychiatric symptoms or causing hypertensive crises.