3-Methoxytyramine (3-MT), also known as 3-methoxy-4-hydroxyphenethylamine, is a human

trace amine Trace amines are an endogenous group of trace amine-associated receptor 1 (TAAR1) agonists – and hence, monoaminergic neuromodulators – that are structurally and metabolically related to classical monoamine neurotransmitters. Compared to ...

and the major

metabolite In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...

of the

monoamine neurotransmitter Monoamine neurotransmitters are neurotransmitters and neuromodulators that contain one amino group connected to an aromatic ring by a two-carbon chain (such as -CH2-CH2-). Examples are dopamine, norepinephrine and serotonin. All monoamines ...

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized ...

. It is formed by the introduction of a

methyl group In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated a ...

to dopamine by the

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

catechol-''O''-methyltransferase (COMT). 3-MT can be further metabolized by the enzyme

monoamine oxidase Monoamine oxidases (MAO) () are a family of enzymes that catalyze the oxidation of monoamines, employing oxygen to clip off their amine group. They are found bound to the outer membrane of mitochondria in most cell types of the body. The fi ...

(MAO) to form homovanillic acid (HVA), which is then typically excreted in the urine.

Occurrence

3-Methoxytyramine occurs naturally in the prickly pear cactus (genus ''Opuntia''), and is in general widespread throughout the

Cactaceae A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

. It has also been found in crown gall tumors on ''Nicotiana'' sp. In humans, 3-methoxytyramine is a

that occurs as a

Biological activity

Originally thought to be physiologically inactive, 3-MT was subsequently found to act as an

agonist An agonist is a chemical that activates a Receptor (biochemistry), receptor to produce a biological response. Receptors are Cell (biology), cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an R ...

of the rodent and human TAAR1. 3-MT can induce weak hyperlocomotion in mice and this effect is partially attenuated in TAAR1

knockout mice A knockout mouse, or knock-out mouse, is a genetically modified mouse (''Mus musculus'') in which researchers have inactivated, or " knocked out", an existing gene by replacing it or disrupting it with an artificial piece of DNA. They are importan ...

References

{{DEFAULTSORT:Methoxytyramine, 3- Methoxyphenethylamines Phenethylamine alkaloids Phenols TAAR1 agonists Trace amines Aminoethyl compounds

Occurrence

Biological activity

See also

References