From Wikipedia, the free encyclopedia
Jump to: navigation, search
Skeletal formula of 3-methoxytyramine
Ball-and-stick model of the 3-methoxytyramine molecule
IUPAC name
Other names
3D model (JSmol)
ECHA InfoCard 100.122.789
MeSH 3-methoxytyramine
Molar mass 167.21 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references

3-Methoxytyramine (3-MT), also known as 3-methoxy-4-hydroxyphenethylamine, is a human trace amine that occurs as a metabolite of the neurotransmitter dopamine.[1] It is formed by the introduction of a methyl group to dopamine by the enzyme catechol-O-methyl transferase (COMT). 3-MT can be further metabolized by the enzyme monoamine oxidase (MAO) to form homovanillic acid (HVA), which is then typically excreted in the urine.

Originally thought to be physiologically inactive, 3-MT has recently been shown to act as an agonist of human TAAR1.[1][2]


3-Methoxytyramine occurs naturally in the prickly pear cactus (genus Opuntia),[3] and is in general widespread throughout the Cactaceae.[4] It has also been found in crown gall tumors on Nicotiana sp.[5]

In humans, 3-methoxytyramine is a trace amine that occurs as a metabolite of dopamine.[1]

See also[edit]


  1. ^ a b c Khan MZ, Nawaz W (October 2016). "The emerging roles of human trace amines and human trace amine-associated receptors (hTAARs) in central nervous system". Biomed. Pharmacother. 83: 439–449. doi:10.1016/j.biopha.2016.07.002. PMID 27424325. 
  2. ^ Sotnikova TD, Beaulieu JM, Espinoza S, et al. (2010). "The dopamine metabolite 3-methoxytyramine is a neuromodulator". PLOS ONE. 5 (10): e13452. doi:10.1371/journal.pone.0013452. PMC 2956650Freely accessible. PMID 20976142. 
  3. ^ Neuwinger, Hans Dieter (1996). "Cactaceae". African ethnobotany: poisons and drugs: chemistry, pharmacology, toxicology. CRC Press. p. 271. ISBN 978-3-8261-0077-2.  Retrieved on June 12, 2009 through Google Book Search.
  4. ^ Smith T. A. (1977). "Phenethylamine and related compounds in plants". Phytochemistry. 16: 9–18. doi:10.1016/0031-9422(77)83004-5. 
  5. ^ Mitchell S. D.; Firmin J. L.; Gray D. O. (1984). "Enhanced 3-methoxytyramine levels in crown gall tumours and other undifferentiated plant tissues". Biochem. J. 221: 891–5. doi:10.1042/bj2210891. 
  6. ^ Broadley KJ (March 2010). "The vascular effects of trace amines and amphetamines". Pharmacol. Ther. 125 (3): 363–375. doi:10.1016/j.pharmthera.2009.11.005. PMID 19948186. 
  7. ^ Lindemann L, Hoener MC (May 2005). "A renaissance in trace amines inspired by a novel GPCR family". Trends Pharmacol. Sci. 26 (5): 274–281. doi:10.1016/j.tips.2005.03.007. PMID 15860375. 
  8. ^ Wang X, Li J, Dong G, Yue J (February 2014). "The endogenous substrates of brain CYP2D". Eur. J. Pharmacol. 724: 211–218. doi:10.1016/j.ejphar.2013.12.025. PMID 24374199. The highest level of brain CYP2D activity was found in the substantia nigra ... The in vitro and in vivo studies have shown the contribution of the alternative CYP2D-mediated dopamine synthesis to the concentration of this neurotransmitter although the classic biosynthetic route to dopamine from tyrosine is active. ... Tyramine levels are especially high in the basal ganglia and limbic system, which are thought to be related to individual behavior and emotion (Yu et al., 2003c). ... Rat CYP2D isoforms (2D2/2D4/2D18) are less efficient than human CYP2D6 for the generation of dopamine from p-tyramine. The Km values of the CYP2D isoforms are as follows: CYP2D6 (87–121 μm) ≈ CYP2D2 ≈ CYP2D18 > CYP2D4 (256 μm) for m-tyramine and CYP2D4 (433 μm) > CYP2D2 ≈ CYP2D6 > CYP2D18 (688 μm) for p-tyramine