Homovanillic Acid (HVA)

Elevations of homovanillic acid can be seen with lack of vitamin cofactors for enzymes within the metabolism of dopamine or the production of norepinephrine. Quercetin supplementation can elevate plasma HVA and perhaps urinary excretion.

Dietary flavanols, such as tomatoes, onions, and tea are also known to elevate urinary HVA. Like VMA, urinary HVA is elevated in conditions such as neuroblastoma and neural crest tumors. And, since dopamine regulates emotional and motivational behavior, changes in dopamine levels, and subsequent HVA levels, have been studied in the overall stress response, PTSD, mood disorders, and autism.

Low levels of urinary HVA imply deficient production of dopamine due to decreased amino acid precursors or lack of vitamin cofactors throughout the production cycle. It may also reflect impaired methylation of dopamine to HVA. Low dopamine turnover and low HVA levels are seen in some mood disorders and as an effect of various antidepressants.

Homovanillic acid (HVA) is a major catecholamine metabolite that is produced by a consecutive action of monoamine oxidase and catechol-Omethyltransferase on dopamine. HVA is associated with dopamine levels in the brain. Dopamine (3,4-dihydroxyphenethylamine) is a major excitatory neurotransmitter that functions both as a hormone and a neurotransmitter and plays several important roles in the brain and body. It is synthesized in the brain and kidneys. In the brain, dopamine functions as a neurotransmitter that acts on several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior.