Tyramine

You don't need to be Editor-In-Chief to add or edit content to WikiDoc. You can begin to add to or edit text on this WikiDoc page by clicking on the edit button at the top of this page. Next enter or edit the information that you would like to appear here. Once you are done editing, scroll down and click the Save page button at the bottom of the page.

Jump to: navigation, search
Tyramine
IUPAC name 4-(2-aminoethyl)phenol
Identifiers
CAS number 51-67-2
PubChem 5610
MeSH Tyramine
SMILES C1=CC(=CC=C1CCN)O
Properties
Molecular formula C8H11NO
Molar mass 137.179 g/mol[1]
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Phone:617-525-6884

Please Join in Editing This Page and Apply to be an Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [2] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.


For patient information, click here

Overview

In organic chemistry tyramine (4-hydroxy-phenethylamine, para-tyramine, p-tyramine) is a monoamine compound derived from the amino acid tyrosine.[1]

Occurrence

Tyramine occurs widely in plants and animals and is metabolized by the enzyme monoamine oxidase. In foods, it is often produced by the decarboxylation of tyrosine during fermentation or decay. Foods containing considerable amounts of tyramine include meats (fish, poultry, and beef) that are potentially spoiled or pickled, aged, smoked, fermented, or marinated, most pork (except country [cured ham), chocolate, alcoholic beverages, and fermented foods such as most cheeses (except ricotta, cottage cheese, cream cheese), sour cream, yogurt, tofu, miso soup, soy sauce and soy bean condiments, teriyaki sauce, shrimp paste, sauerkraut, broad (fava) beans, green bean pods, Italian flat (Romano) beans, Chinese (Snow) pea pods, avocados, bananas, eggplant, figs, red plums, raspberries, peanuts, Brazil nuts, coconuts, processed meat, yeast, and red wine.

Metabolism

In humans, if monoamine metabolism is compromised by the use of monoamine oxidase inhibitors (MAOIs) and foods high in tyramine are ingested, a hypertensive crisis can result as tyramine can cause the release of stored monoamines, such as dopamine, norepinephrine, epinephrine. The first signs of this were discovered by a neurologist who noticed his wife, who at the time was on MAOI medication, had severe headaches when eating cheese. For this reason, the crisis is still called the "cheese syndrome," even though other foods can cause the same problem.

Effects

A large dietary intake of tyramine (or a dietary intake of tyramine while taking MAO inhibitors) can cause the 'tyramine pressor response,' which is defined as an increase in systolic blood pressure of 30 mmHg or more. The displacement of norepinephrin(noradrenaline) from neuronal storage vesicles by acute tyramine ingestion is thought to cause the vasoconstriction and increased heart rate and blood pressure of the pressor response.

However, if one has had repeated exposure to tyramine, there is a decreased pressor response; Tyramine is degraded to octopamine, which is subsequently packaged in synaptic vesicles with norepinephrin(noradrenaline). Therefore, after repeated tyramine exposure, these vesicles contain an increased amount of octopamine, and a relativley reduced amount of norepinephrin(noradrenaline). Therefore, when these vesicles are secreted upon tyramine ingestion, there is a decreased pressor response, as less norepinephrin(noradrenaline) is secreted into the synpase, and octopamine does not activate alpha or beta adrenoceptors.

The possibility that tyramine acts directly as a neurotransmitter was revealed by the discovery of a G protein-coupled receptor with high affinity for tyramine, called TA1. The TA1 receptor is found in the brain as well as peripheral tissues, including the kidney. The existence of a receptor with high affinity for tyramine supports the hypothesis that tyramine may also act directly to affect blood pressure regulation.

Migraine

Dietary tyramine intake has also been associated with migraine in select populations, leading many sufferers to restrict foods high in tyramine.[1] Reports on the tyramine-migraine link have been both affirmed and denied. A recent review article found that all past studies affirming a migraine-tyramine connection were scientifically inconclusive, and noted several studies showing no connection. Two studies validated as scientifically sound reported no connection in the population evaluated.

References

See also

ca:Tiramina de:Tyramin fr:Tyramine it:Tiramina

WikiDoc Help Menu

Quick Start..

Editing basics

Advanced editing

Communicating your edits

Help Videos You Can Watch


Acknowledgement and Attribution Regarding Sources of Content

Some of the initial content on this page may be incorporated in part from copyleft sources in the public domain including wikis such as Wikipedia and AskDrWiki. Drug information for patients came from the The National Library of Medicine. Infectious disease information may have come from the Centers for Disease Control (CDC). Differential Diagnoses are drawn from clinicians as well as an amalgamation of 3 sources: 1.The Disease Database; 2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3; 3. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:7 .

Personal tools
In other languages