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Dopamine is a neurotransmitter with multiple roles in the body.

Dopamine synthesis[edit | edit source]

Dopamine is synthesized in neurons and the adrenal glands.

L-Phenylalanine → L-TyrosineL-DOPA → Dopamine

Dopamine is incapable of crossing the blood-brain barrier so it must be produced in the brain for neuronal activity, or peripherally for peripheral activity.

Peripheral dopamine is produced by the adrenal glands and the gut.

BH4 is a cofactor in the conversion of L-Phenylalanine to L-Tyrosine and L-Tyrosine to L-DOPA. The availability of BH4 is dependent on the methylation cycle.

Dopamine is a precursor to norepinephrine and epinephrine.

Iron is important in the expression of dopamine receptors in the brain[1] and is also a cofactor in for tyrosine hydroxylase, the enzyme that catalyzes the conversion of tyrosine to L-DOPA.

Nervous system[edit | edit source]

Dopamine plays a role in executive function, motor control, motivation, arousal. The largest source of dopamine in the brain is in the substantia nigra and ventral segmental area, both components of the basal ganglia.

Immune system[edit | edit source]

Dopamine reduces systemic inflammation by blocking inflammasome activation.[2][3]

Dopamine has a role in the activity of lymphocytes. It activates native t cells but inhibits the activity of activated t cells.[4] However, dopamine may also induce the release of interleukin-17 in rheumatoid arthritis.[5]

Inflammation may also have a role in dopamine production. A study of Hepatitis C patients found that interferon alpha treatment resulted in significantly increased levels of dihydrobiopterin (BH2) and decreased tetrahydrobiopterin (BH4) as well as reduced conversion of phenylalanine to tyrosine in the cerebrospinal fluid, which are associated with decreased dopamine in the brain.[6]

Chronic fatigue syndrome[edit | edit source]

Studies have found lower levels of the dopamine precursor tyrosine[7] and reduced activation in the basal ganglia[8][9] , the region of the brain with the highest concentration of dopaminergic neurons.

Fibromyalgia[edit | edit source]

Small, preliminary studies have found evidence of abnormal dopamine metabolism in the brains of fibromyalgia patients.[10][11][12][13]

Other conditions[edit | edit source]

Parkinson's disease involves the loss of dopaminergic neurons in the midbrain and subsequently reduced dopamine. Schizophrenia, ADHD and restless leg syndrome are also associated with altered dopamine.

Cerebralspinal iron is decreased in restless legs syndrome despite normal serum levels.[14]

In addition to its neurological effects, reduced dopamine may also have immunological effects in these diseases.

Altered dopamine metabolism may play a role in a number of autoimmune diseases.[15]

Dopaminergic neurons are thought to play a role in epileptic seizures arising from the limbic system.[16]

Altering dopamine levels[edit | edit source]

Mice fed a ketogenic diet had increased activity of dopaminergic neurons.[17]

List of drugs and supplements with dopaminergic effects.

References[edit | edit source]

cofactor - A substance that acts with another substance to bring about certain effects. In biochemistry, a cofactor is a molecule that is necessary for a given biochemical reaction, but is not an enzyme or substrate of the reaction.

enzyme - a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction.

chronic fatigue syndrome (CFS) - A controversial term, invented by the U.S. Centers for Disease Control, that generally refers to a collection of symptoms as “fatigue”. There have been multiple attempts to come up with a set of diagnostic criteria to define this term, but few of those diagnostic criteria are currently in use. Previous attempts to define this term include the Fukuda criteria and the Oxford criteria. Some view the term as a useful diagnostic category for people with long-term fatigue of unexplained origin. Others view the term as a derogatory term borne out of animus towards patients. Some view the term as a synonym of myalgic encephalomyelitis, while others view myalgic encephalomyelitis as a distinct disease.

serum - The clear yellowish fluid that remains from blood plasma after clotting factors have been removed by clot formation. (Blood plasma is simply blood that has had its blood cells removed.)

The information provided at this site is not intended to diagnose or treat any illness.
From MEpedia, a crowd-sourced encyclopedia of ME and CFS science and history.