Dopamine
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| + | A [[neurotransmitter]] associated with [[Kinesis (biology) |movement]], [[attention]], [[learning]], and the [[brain]]'s [[pleasure]] and [[reward system]]. | ||
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| + | "[[L Dopa fixed me, all right]]." | ||
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| - | *[[Arnold Rijpens]], The Originals | + | |
| - | *[[Banyan]] trees | + | '''Dopamine''' ('''DA''', a contraction of '''3,4-<u>d</u>ihydr<u>o</u>xy<u>p</u>henethyl<u>amine</u>''') is an [[organic compound|organic chemical]] of the [[catecholamine]] and [[phenethylamine]] families that plays several important roles in the brain and body. It is an [[amine]] synthesized by removing a [[carboxyl group]] from a molecule of its [[precursor (chemistry)|precursor chemical]] [[L-DOPA]], which is [[biosynthesis|synthesized]] in the brain and kidneys. Dopamine is also synthesized in plants and most animals. In the [[brain]], dopamine functions as a [[neurotransmitter]]—a chemical released by [[neuron]]s (nerve cells) to send signals to other nerve cells. The brain includes several distinct [[dopaminergic pathway|dopamine pathways]], one of which plays a major role in the motivational component of [[reward system|reward-motivated behavior]]. The anticipation of most types of rewards increases the level of dopamine in the brain, and many [[addiction|addictive]] [[Psychoactive drug|drugs]] increase dopamine release or block its reuptake into neurons following release. Other brain dopamine pathways are involved in [[motor system|motor control]] and in controlling the release of various hormones. These pathways and [[dopaminergic cell groups|cell groups]] form a dopamine system which is [[neuromodulation|neuromodulatory]]. |
| - | *[[Dopamine]] | + | |
| - | *[[Sonian]] | + | In popular culture and media, dopamine is often seen as the main chemical of pleasure, but the current opinion in pharmacology is that dopamine instead affects [[Motivational salience|incentive salience]], meaning that it signals the value of an outcome which motivates the organism to achieve an outcome. |
| - | *[[Abilify]] | + | |
| + | Outside the [[central nervous system]], dopamine functions primarily as a local [[neurotransmitter|chemical messenger]]. In blood vessels, it inhibits [[norepinephrine]] release and acts as a [[vasodilator]] (at normal concentrations); in the kidneys, it increases sodium excretion and urine output; in the [[pancreas]], it reduces insulin production; in the digestive system, it reduces [[Gastrointestinal physiology#Motility|gastrointestinal motility]] and protects [[intestinal mucosa]]; and in the immune system, it reduces the activity of [[lymphocytes]]. With the exception of the blood vessels, dopamine in each of these peripheral systems is synthesized locally and exerts its effects near the cells that release it. | ||
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| + | Several important diseases of the nervous system are associated with dysfunctions of the dopamine system, and some of the key medications used to treat them work by altering the effects of dopamine. [[Parkinson's disease]], a degenerative condition causing tremor and motor impairment, is caused by a loss of dopamine-secreting neurons in an area of the [[midbrain]] called the [[substantia nigra]]. Its metabolic precursor L-DOPA can be manufactured; ''Levodopa'', a pure form of L-DOPA, is the most widely used treatment for Parkinson's. There is evidence that [[schizophrenia]] involves altered levels of dopamine activity, and most [[antipsychotic|antipsychotic drugs]] used to treat this are [[dopamine antagonist]]s which reduce dopamine activity. Similar dopamine antagonist drugs are also some of the most effective [[antiemetic|anti-nausea agents]]. [[Restless legs syndrome]] and [[attention deficit hyperactivity disorder]] (ADHD) are associated with decreased dopamine activity. [[Dopaminergic]] [[sympathomimetic drug|stimulants]] can be addictive in high doses, but some are used at lower doses to treat ADHD. [[Dopamine (medication)|Dopamine]] itself is available as a manufactured [[pharmaceutical drug|medication]] for [[intravenous therapy|intravenous injection]]: although it [[Blood–brain barrier|cannot reach the brain from the bloodstream]], its peripheral effects make it useful in the treatment of [[heart failure]] or [[shock (circulatory)|shock]], especially in newborn babies. | ||
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| + | ==History== | ||
| + | Dopamine was first synthesized in 1910 by [[George Barger]] and [[James Ewens]] at [[Wellcome Trust|Wellcome]] Laboratories in London, England. It was named dopamine because it is a [[monoamine]] whose [[Precursor chemical|precursor]] in the Barger-Ewens synthesis is 3,4-''d''ihydr''o''xy''p''henyl''a''lanine (levodopamine or [[L-DOPA]]). Dopamine's function as a neurotransmitter was first recognized in 1958 by [[Arvid Carlsson]] and [[Nils-Åke Hillarp]] at the Laboratory for Chemical Pharmacology of the National Heart Institute of [[Sweden]]. Carlsson was awarded the 2000 [[Nobel Prize in Physiology or Medicine]] for showing that dopamine is not only a precursor of [[norepinephrine]] (noradrenaline) and [[epinephrine]] (adrenaline), but also a neurotransmitter. | ||
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| + | == See also == | ||
| + | * [[Substance use disorder|Addiction]] | ||
| + | * [[Amphetamine]] | ||
| + | * [[Antipsychotic]] | ||
| + | * [[Catecholamine]] | ||
| + | * [[Catechol-O-methyl transferase]] | ||
| + | * [[Classical conditioning]] | ||
| + | * [[Cocaine]] | ||
| + | * [[Depression (mood)|Depression]] | ||
| + | * [[Dopamine hypothesis of schizophrenia]] | ||
| + | * [[Dopamine reuptake inhibitor]] | ||
| + | * [[Epinine]] (N-methyldopamine) | ||
| + | * [[Limbic system]] | ||
| + | * [[Methylphenidate]] | ||
| + | * [[N,N-Dimethyldopamine]] | ||
| + | * [[Neurotransmitter]] | ||
| + | * [[Operant conditioning]] | ||
| + | * [[Parkinson's disease]] | ||
| + | * [[Prolactinoma]] | ||
| + | * [[Schizophrenia]] | ||
| + | * [[Selegiline]] | ||
| + | * [[Serotonin]] | ||
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Current revision
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A neurotransmitter associated with movement, attention, learning, and the brain's pleasure and reward system. |
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Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is an organic chemical of the catecholamine and phenethylamine families that plays several important roles in the brain and body. It is an amine synthesized by removing a carboxyl group from a molecule of its precursor chemical L-DOPA, which is synthesized in the brain and kidneys. Dopamine is also synthesized in plants and most animals. In the brain, dopamine functions as a neurotransmitter—a chemical released by neurons (nerve cells) to send signals to other nerve cells. The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior. The anticipation of most types of rewards increases the level of dopamine in the brain, and many addictive drugs increase dopamine release or block its reuptake into neurons following release. Other brain dopamine pathways are involved in motor control and in controlling the release of various hormones. These pathways and cell groups form a dopamine system which is neuromodulatory.
In popular culture and media, dopamine is often seen as the main chemical of pleasure, but the current opinion in pharmacology is that dopamine instead affects incentive salience, meaning that it signals the value of an outcome which motivates the organism to achieve an outcome.
Outside the central nervous system, dopamine functions primarily as a local chemical messenger. In blood vessels, it inhibits norepinephrine release and acts as a vasodilator (at normal concentrations); in the kidneys, it increases sodium excretion and urine output; in the pancreas, it reduces insulin production; in the digestive system, it reduces gastrointestinal motility and protects intestinal mucosa; and in the immune system, it reduces the activity of lymphocytes. With the exception of the blood vessels, dopamine in each of these peripheral systems is synthesized locally and exerts its effects near the cells that release it.
Several important diseases of the nervous system are associated with dysfunctions of the dopamine system, and some of the key medications used to treat them work by altering the effects of dopamine. Parkinson's disease, a degenerative condition causing tremor and motor impairment, is caused by a loss of dopamine-secreting neurons in an area of the midbrain called the substantia nigra. Its metabolic precursor L-DOPA can be manufactured; Levodopa, a pure form of L-DOPA, is the most widely used treatment for Parkinson's. There is evidence that schizophrenia involves altered levels of dopamine activity, and most antipsychotic drugs used to treat this are dopamine antagonists which reduce dopamine activity. Similar dopamine antagonist drugs are also some of the most effective anti-nausea agents. Restless legs syndrome and attention deficit hyperactivity disorder (ADHD) are associated with decreased dopamine activity. Dopaminergic stimulants can be addictive in high doses, but some are used at lower doses to treat ADHD. Dopamine itself is available as a manufactured medication for intravenous injection: although it cannot reach the brain from the bloodstream, its peripheral effects make it useful in the treatment of heart failure or shock, especially in newborn babies.
History
Dopamine was first synthesized in 1910 by George Barger and James Ewens at Wellcome Laboratories in London, England. It was named dopamine because it is a monoamine whose precursor in the Barger-Ewens synthesis is 3,4-dihydroxyphenylalanine (levodopamine or L-DOPA). Dopamine's function as a neurotransmitter was first recognized in 1958 by Arvid Carlsson and Nils-Åke Hillarp at the Laboratory for Chemical Pharmacology of the National Heart Institute of Sweden. Carlsson was awarded the 2000 Nobel Prize in Physiology or Medicine for showing that dopamine is not only a precursor of norepinephrine (noradrenaline) and epinephrine (adrenaline), but also a neurotransmitter.
See also
- Addiction
- Amphetamine
- Antipsychotic
- Catecholamine
- Catechol-O-methyl transferase
- Classical conditioning
- Cocaine
- Depression
- Dopamine hypothesis of schizophrenia
- Dopamine reuptake inhibitor
- Epinine (N-methyldopamine)
- Limbic system
- Methylphenidate
- N,N-Dimethyldopamine
- Neurotransmitter
- Operant conditioning
- Parkinson's disease
- Prolactinoma
- Schizophrenia
- Selegiline
- Serotonin
