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Encyclopedia > Dopamine
Dopamine
IUPAC name 4-(2-aminoethyl)benzene-1,2-diol
Other names 2-(3,4-dihydroxyphenyl)ethylamine;
3,4-dihydroxyphenethylamine;
3-hydroxytyramine; DA; Intropin
Revivan; Oxytyramine
Identifiers
CAS number 51-61-6
PubChem 681
SMILES C1=CC(=C(C=C1CCN)O)O
Properties
Molecular formula C8H11NO2
Molar mass 153.178
Melting point

128 °C (401 K) Look up Dopamine in Wiktionary, the free dictionary. ... Image File history File links Dopamin_-_Dopamine. ... Image File history File links Size of this preview: 800 × 548 pixelsFull resolution (916 × 628 pixel, file size: 112 KB, MIME type: image/png) Please see the file description page for further information. ... IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... PubChem is a database of chemical molecules. ... The simplified molecular input line entry specification or SMILES is a specification for unambiguously describing the structure of chemical molecules using short ASCII strings. ... A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... Molar mass is the mass of one mole of a chemical element or chemical compound. ... The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. ...

Solubility in water 60.0 g/100 ml (? °C), solid
Hazards
R/S statement R: 36/37/38
S: 26-36
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Dopamine is a hormone and neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In chemical structure, it is a phenethylamine. Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Risk and Safety Statements, also known as R/S statements, R/S numbers, R/S phrases, and R/S sentences, is a system of hazard codes and phrases for labeling dangerous chemicals and compounds. ... R-phrases are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations. ... S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. ... The plimsoll symbol as used in shipping In chemistry, the standard state of a material is its state at 1 bar (100 kilopascals exactly). ... For other uses, see Hormone (disambiguation). ... Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ... Phenethylamine, or β-Phenylethylamine, is an alkaloid and monoamine. ...


In the brain, dopamine functions as a neurotransmitter, activating the five types of dopamine receptors - D1, D2, D3, D4 and D5, and their variants. Dopamine is produced in several areas of the brain, including the substantia nigra. Dopamine is also a neurohormone released by the hypothalamus. Its main function as a hormone is to inhibit the release of prolactin from the anterior lobe of the pituitary. The human brain controls the central nervous system (CNS), by way of the cranial nerves and spinal cord, the peripheral nervous system (PNS) and regulates virtually all human activity. ... Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ... The dopamine receptors are a class of metabotropic G-protein-coupled receptors with the neurotransmitter dopamine as their endogenous ligand. ... The substantia nigra, (Latin for black substance, Soemering) or locus niger is a heterogeneous portion of the midbrain, separating the pes (foot) from the tegmentum (covering), and a major element of the basal ganglia system. ... A neurohormone is any hormone produced by neurosecretory cells, usually in the brain. ... The hypothalamus links the nervous system to the endocrine system via the pituitary gland (hypophysis). ... Prolactin (PRL) is a peptide hormone primarily associated with lactation. ... Located at the base of the skull, the pituitary gland is protected by a bony structure called the sella turcica. ...


Dopamine can be supplied as a medication that acts on the sympathetic nervous system, producing effects such as increased heart rate and blood pressure. However, since dopamine cannot cross the blood-brain barrier, dopamine given as a drug does not directly affect the central nervous system. To increase the amount of dopamine in the brains of patients with diseases such as Parkinson's disease and Dopa-Responsive Dystonia, L-DOPA (levodopa), which is the precursor of dopamine, can be given because it can cross the blood-brain barrier. This article does not cite any references or sources. ... The Sympathetic Nervous System (SNS) is a branch of the autonomic nervous system. ... The Human Nervous System. ... The heart and lungs, from an older edition of Grays Anatomy. ... A sphygmomanometer, a device used for measuring arterial pressure. ... The blood-brain barrier (BBB) is a membranic structure that acts primarily to protect the brain from chemicals in the blood, while still allowing essential metabolic function. ... A diagram showing the CNS: 1. ... Dystonia is a neurological movement disorder in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. ... Levodopa (INN) or L-DOPA (3,4-dihydroxy-L-phenylalanine) is an intermediate in dopamine biosynthesis. ... The blood-brain barrier (BBB) is a membranic structure that acts primarily to protect the brain from chemicals in the blood, while still allowing essential metabolic function. ...

Contents

History

Dopamine was discovered by Arvid Carlsson and Nils-Åke Hillarp at the Laboratory for Chemical Pharmacology of the National Heart Institute of Sweden, in 1952. It was named Dopamine because it was a monoamine, and its synthetic precursor was 3,4-dihydroxyphenylalanine (L-DOPA).[1] Arvid Carlsson was awarded the 2000 Nobel Prize in Physiology or Medicine for showing that dopamine is not just a precursor of noradrenaline and adrenaline but a neurotransmitter, as well. Arvid Carlsson (b. ... In biochemistry, monoamines are a group of organic compounds containing only one amino group. ... // Therapeutic use L-DOPA is used to replace dopamine lost in Parkinsons disease because dopamine itself cannot cross the blood-brain barrierwhere its precursor can. ... Arvid Carlsson (b. ... Year 2000 (MM) was a leap year starting on Saturday (link will display full 2000 Gregorian calendar). ... Emil Adolf von Behring was the first person to receive the Nobel Prize in Physiology or Medicine, for his work on the treatment of diphtheria. ... Norepinephrine, known as noradrenaline outside the USA, is a catecholamine and a phenethylamine with chemical formula C8H11NO3. ... Epinephrine (INN) or adrenaline (BAN) is a hormone and a neurotransmitter. ...


Biochemistry

Name and family

Dopamine has the chemical formula C6H3(OH)2-CH2-CH2-NH2. Its chemical name is "4-(2-aminoethyl)benzene-1,2-diol" and its abbreviation is "DA."


As a member of the catecholamine family, dopamine is a precursor to norepinephrine (noradrenaline) and then epinephrine (adrenaline) in the biosynthetic pathways for these neurotransmitters. tyrosine is the precursor of catecholamines epinephrine norepinephrine dopamine Synthesis Catecholamines are chemical compounds derived from the amino acid tyrosine containing catechol and amine groups. ... Norepinephrine (INN)(abbr. ... Adrenaline redirects here. ...


Biosynthesis

Dopamine is biosynthesized in the body (mainly by nervous tissue and the medulla of the adrenal glands) first by the hydration of the amino acid L-tyrosine to L-DOPA via the enzyme tyrosine 3-monooxygenase, also known as tyrosine hydroxylase, and then by the decarboxylation of L-DOPA by aromatic L-amino acid decarboxylase (which is often referred to as dopa decarboxylase). In some neurons, dopamine is further processed into norepinephrine by dopamine beta-hydroxylase. In mammals, the adrenal glands are the triangle-shaped endocrine glands that sit atop the kidneys. ... In mammals, the adrenal glands (also known as suprarenal glands) are the triangle-shaped endocrine glands that sit on top of the kidneys; their name indicates that position (ad-, near or at + -renes, kidneys). They are chiefly responsible for regulating the stress response through the synthesis of corticosteroids and catecholamines... Tyrosine (from the Greek tyros, meaning cheese, as it was first discovered in 1846 by German chemist Justus von Liebig in cheese[1][2]), 4-hydroxyphenylalanine, or 2-amino-3(4-hydroxyphenyl)-propanoic acid, is one of the 20 amino acids that are used by cells to synthesize proteins. ... Tyrosine Hydroxylase is the enzyme responsible for catalysing the conversion of L-tyrosine, an amino acid, to dihydroxyphenylalanine (DOPA), a precursor to Dopamine in the process the body uses to synthesise adrenaline (epinephrin). ... A Decarboxylation is any chemical reaction in which a carboxyl group (-COOH) is split off from a compound as carbon dioxide (CO2). ... // Therapeutic use L-DOPA is used to replace dopamine lost in Parkinsons disease because dopamine itself cannot cross the blood-brain barrierwhere its precursor can. ... Aromatic L-amino acid decarboxylase (EC 4. ... Norepinephrine (INN)(abbr. ... Dopamine β-hydroxylase (DBH) is an enzyme that converts dopamine to norepinephrine: DBH is a 290 kDa copper-containing oxygenase consisting of four identical subunits, and its activity requires ascorbate as a cofactor. ...


In neurons, dopamine is packaged after synthesis into vesicles, which are then released into the synapse in response to the presynaptic action potential. This article is about cells in the nervous system. ... In cell biology, a vesicle is a relatively small and enclosed compartment, separated from the cytosol by at least one lipid bilayer. ... Illustration of the major elements in a prototypical synapse. ... A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ...


Inactivation and degradation

Dopamine is inactivated by reuptake via the dopamine transporter, then enzymatic breakdown by catechol-O-methyl transferase (COMT) and monoamine oxidase (MAO). Dopamine that is not broken down by enzymes is repackaged into vesicles for reuse. The dopamine transporter or DAT is a monoamine transporter that is specific for clearing the neurotransmitter dopamine out of the synaptic cleft and into a glial cell or the presynaptic neuron. ... Catechol-O-methyl transferase (COMT) (EC 2. ... Monoamine oxidase Monoamine oxidases (singular abbreviation MAO) (EC 1. ...


Dopamine may also simply diffuse away from the synapse. This article is about the physical mechanism of diffusion. ... Illustration of the major elements in a prototypical synapse. ...

Image File history File links Dopamine_degradation. ... Image File history File links Dopamine_degradation. ...

Functions in the brain

Dopamine has many functions in the brain, including important roles in behavior and cognition, motor activity, motivation and reward, regulation of milk production, sleep, mood, attention, and learning. Dopaminergic neurons (i.e., neurons whose primary neurotransmitter is dopamine) are present chiefly in the ventral tegmental area (VTA) of the midbrain, substantia nigra pars compacta, and arcuate nucleus of the hypothalamus. Look up Cognition in Wiktionary, the free dictionary. ... Look up Motivation in Wiktionary, the free dictionary. ... A reward is something that an animal will work to obtain, for example, food. ... For other uses, see Sleep (disambiguation). ... A mood is a relatively lasting emotional or affective state. ... This article is about psychological concept of attention. ... Learning is the acquisition and development of memories and behaviors, including skills, knowledge, understanding, values, and wisdom. ... Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ... The ventral tegmentum or the ventral tegmental area (VTA) is part of the midbrain, lying close to the substantia nigra and the red nucleus. ... In biological anatomy, the mesencephalon (or midbrain) is the middle of three vesicles that arise from the neural tube that forms the brain of developing animals. ... The substantia nigra, (Latin for black substance, Soemering) or locus niger is a heterogeneous portion of the midbrain, separating the pes (foot) from the tegmentum (covering), and a major element of the basal ganglia system. ... The arcuate nucleus is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. ... The hypothalamus links the nervous system to the endocrine system via the pituitary gland (hypophysis). ...


The VTA and nucleus accumbens are central to the brain reward system.[2] Dopamine neurons in the primate brain are found in the substantia nigra pars compacta and the ventral tegmental area. The phasic responses of dopamine neurons are observed when an unexpected reward is presented. These responses transfer to the onset of a conditioned stimulus after repeated pairings with the reward. Further, dopamine neurons are depressed when the expected reward is omitted. Thus, dopamine neurons seem to encode the prediction error of rewarding outcomes. In nature, we learn to repeat behaviors that lead to maximize rewards. Dopamine is therefore believed by many to provide a teaching signal to parts of the brain responsible for acquiring new behavior. Temporal difference learning provides a computational model describing how the prediction error of dopamine neurons is used as a teaching signal. The nucleus accumbens (NAcc), also known as the accumbens nucleus or as the nucleus accumbens septi (Latin for nucleus leaning against the septum), is a collection of neurons located where the head of the caudate and the anterior portion of the putamen meet just lateral to the septum pellucidum. ... A reward is something that an animal will work to obtain, for example, food. ... The ventral tegmentum or the ventral tegmental area (VTA) is part of the midbrain, lying close to the substantia nigra and the red nucleus. ... It has been suggested that eye blink conditioning be merged into this article or section. ... Temporal difference learning is a prediction method. ...


In insects, a similar reward system exists, using octopamine, a chemical relative of dopamine.[3] Octopamine is a biogenic amine which is closely related to noradrenaline, and has a similar action to dopamine. ... Quantitative structure-activity relationship (QSAR) is the process by which chemical structure is quantitatively correlated with a well defined process, such as biological activity or chemical reactivity. ...


Movement

Via the dopamine receptors D1, D2, D3, D4 and D5, dopamine reduces the influence of the indirect pathway, and increases the actions of the direct pathway within the basal ganglia. Insufficient dopamine biosynthesis in the dopaminergic neurons can cause Parkinson's disease, in which a person loses the ability to execute smooth, controlled movements. The phasic dopaminergic activation seems to be crucial with respect to a lasting internal encoding of motor skills (Beck, 2005). The dopamine receptors are a class of metabotropic G-protein-coupled receptors with the neurotransmitter dopamine as their endogenous ligand. ...


Cognition and frontal cortex

In the frontal lobes, dopamine controls the flow of information from other areas of the brain. Dopamine disorders in this region of the brain can cause a decline in neurocognitive functions, especially memory, attention, and problem-solving. Reduced dopamine concentrations in the prefrontal cortex are thought to contribute to attention deficit disorder. On the converse, however, anti-psychotic medications act as dopamine antagonists and are used in the treatment of positive symptoms in schizophrenia. The frontal lobe is an area in the brain of mammals. ... Neurocognitive is a term used to describe cognitive functions closely linked to the function of particular areas, neural pathways, or cortical networks in the brain. ... For other uses, see Memory (disambiguation). ... This article is about psychological concept of attention. ... Problem solving forms part of thinking. ... DISCLAIMER Please remember that Wikipedia is offered for informational use only. ...


Regulating prolactin secretion

Dopamine is the primary neuroendocrine regulator of the secretion of prolactin from the anterior pituitary gland. Dopamine produced by neurons in the arcuate nucleus of the hypothalamus is secreted into the hypothalamo-hypophysial blood vessels of the median eminence, which supply the pituitary gland. The lactotrope cells that produce prolactin, in the absence of dopamine, secrete prolactin continuously; dopamine inhibits this secretion. Thus, in the context of regulating prolactin secretion, dopamine is occasionally called prolactin-inhibiting factor (PIF), prolactin-inhibiting hormone (PIH), or prolactostatin. Prolactin also seems to inhibit dopamine release, such as after orgasm, and is chiefly responsible for the refractory period. Prolactin (PRL) is a peptide hormone primarily associated with lactation. ... The anterior pituitary (also called the adenohypophysis, from Greek adeno, gland; hypo, under; physis, growth; hence, glandular undergrowth) comprises the anterior lobe of the pituitary gland and is part of the endocrine system. ... The arcuate nucleus is an aggregation of neurons in the mediobasal hypothalamus, adjacent to the third ventricle and the median eminence. ... The hypothalamus links the nervous system to the endocrine system via the pituitary gland (hypophysis). ... Median Eminence The median eminence is part of the inferior boundary for the hypothalamus. ... Prolactin (PRL) is a peptide hormone primarily associated with lactation. ... Prolactin (PRL) is a peptide hormone primarily associated with lactation. ... // An orgasm (sexual climax) is the conclusion of the plateau phase of the sexual response cycle, and is experienced by both males and females. ... In sexual intercourse, the refractory period is a recovery phase after orgasm during which it is physiologically impossible for a person to experience continued arousal or additional orgasms. ...


Motivation and pleasure

Look up Motivation in Wiktionary, the free dictionary. ...

Reinforcement

Dopamine is commonly associated with the pleasure system of the brain, providing feelings of enjoyment and reinforcement to motivate a person proactively to perform certain activities. Dopamine is released (particularly in areas such as the nucleus accumbens and ventral tegmental area) by naturally rewarding experiences such as food, sex,[4][5] use of certain drugs and neutral stimuli that become associated with them. This theory is often discussed in terms of drugs such as cocaine and amphetamines, which seem to directly or indirectly lead to the increase of dopamine in these areas, and in relation to neurobiological theories of chemical addiction, arguing that these dopamine pathways are pathologically altered in addicted persons. In operant conditioning, reinforcement is an increase in the strength of a response following the presentation of a stimulus contingent on that response. ... The nucleus accumbens (NAcc), also known as the accumbens nucleus or as the nucleus accumbens septi (Latin for nucleus leaning against the septum), is a collection of neurons located where the head of the caudate and the anterior portion of the putamen meet just lateral to the septum pellucidum. ... The ventral tegmentum or the ventral tegmental area (VTA) is part of the midbrain, lying close to the substantia nigra and the red nucleus. ... Sexual behavior is a form of physical intimacy that may be directed to reproduction (one possible goal of sexual intercourse) and/or to the enjoyment of activity involving sexual gratification. ... Neutral stimulus: a stimulus which iniatially produces no specific response other than provoking attention. ... It has been suggested that eye blink conditioning be merged into this article or section. ... Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. ... Amphetamine or Amfetamine(Alpha-Methyl-PHenEThylAMINE), also known as beta-phenyl-isopropylamine and benzedrine, is a prescription stimulant commonly used to treat Attention-deficit hyperactivity disorder (ADHD) in adults and children. ... Neurobiology is the study of cells of the nervous system and the organization of these cells into functional circuits that process information and mediate behavior. ...


Reuptake inhibition, expulsion

However, cocaine and amphetamine influence separate mechanisms of action. Cocaine is a dopamine transporter blocker that competitively inhibits dopamine uptake to increase the lifetime of dopamine and augments an overabundance of dopamine (an increase of up to 150%) within the parameters of the dopamine neurotransmitters. The dopamine transporter or DAT is a monoamine transporter that is specific for clearing the neurotransmitter dopamine out of the synaptic cleft and into a glial cell or the presynaptic neuron. ...


Like cocaine, amphetamines increase the concentration of dopamine in the synaptic gap, but by a different mechanism. Amphetamines are similar in structure to dopamine, and so can enter the terminal button of the presynaptic neuron via its dopamine transporters as well as by diffusing through the neural membrane directly. When entering inside the presynaptic neuron, amphetamines force the dopamine molecules out of their storage vesicles and expel them into the synaptic gap by making the dopamine transporters work in reverse. Dopamine's role in experiencing pleasure has been questioned by several researchers. It has been argued that dopamine is more associated with anticipatory desire and motivation (commonly referred to as "wanting") as opposed to actual consummatory pleasure (commonly referred to as "liking"). Dopamine is not released when unpleasant or aversive stimuli are encountered, and so motivates towards the pleasure of avoiding or removing the unpleasant stimuli.


Animal studies

Clues to dopamine's role in motivation, desire, and pleasure have come from studies performed on animals. In one such study, rats were depleted of dopamine by up to 99% in the nucleus accumbens and neostriatum using 6-hydroxydopamine.[6] With this large reduction in dopamine, the rats would no longer eat by their own volition. The researchers then force-fed the rats food and noted whether they had the proper facial expressions indicating whether they liked or disliked it. The researchers of this study concluded that the reduction in dopamine did not reduce the rat's consummatory pleasure, only the desire to actually eat. In another study, mutant hyperdopaminergic (increased dopamine) mice show higher "wanting" but not "liking" of sweet rewards.[7] The nucleus accumbens (NAcc), also known as the accumbens nucleus or as the nucleus accumbens septi (Latin for nucleus leaning against the septum), is a collection of neurons located where the head of the caudate and the anterior portion of the putamen meet just lateral to the septum pellucidum. ... We dont have an article called Neostriatum Start this article Search for Neostriatum in. ...


Dopamine reducing drugs in humans

In humans, however, drugs that reduce dopamine activity (neuroleptics, e.g., some antipsychotics) have been shown to reduce motivation, as well as cause anhedonia (the inability to experience pleasure).[8] Conversely the selective D2/D3 agonists pramipexole and ropinirole have anti-anhedonic properties as measured by the Snaith-Hamilton Pleasure Scale.[9] (The Snaith-Hamilton-Pleasure-Scale (SHAPS), introduced in English in 1995, assesses self-reported anhedonia in psychiatric patients.) The term antipsychotic is applied to a group of drugs used to treat psychosis. ... In psychology, anhedonia is a patients inability to experience pleasure from normally pleasurable life events such as eating, exercise, and social/sexual interactions. ... Pramipexole (INN, trade names Mirapex® and Sifrol®) is a medication indicated for treating Parkinsons disease and restless legs syndrome (RLS). ... Requip (ropinirole) is so far the only medication in the United States with an FDA approved indication for the treatment of Restless Legs Syndrome. ...


Opioid and cannabinoid transmission

Opioid and cannabinoid transmission instead of dopamine may modulate consummatory pleasure and food palatability (liking).[10] This could explain why animals' "liking" of food is independent of brain dopamine concentration. Other consummatory pleasures, however, may be more associated with dopamine. One study found that both anticipatory and consummatory measures of sexual behavior (male rats) were disrupted by DA receptor antagonists.[11] Libido can be increased by drugs that affect dopamine, but not by drugs that affect opioid peptides or other neurotransmitters. An opioid is a chemical substance that has a morphine-like action in the body. ... Cannabinoids are a group of chemicals which activate the bodys cannabinoid receptors. ...


Sociability

Sociability is also closely tied to dopamine neurotransmission. Low D2 receptor-binding is found in people with social anxiety. Traits common to negative schizophrenia (social withdrawal, apathy, anhedonia) are thought to be related to a hypodopaminergic state in certain areas of the brain. In instances of bipolar, manic subjects can become hypersocial, as well as hypersexual. This is also credited to an increase in dopamine, because mania alleviates from dopamine-blocking antipsychotics. Social anxiety is an experience of fear, apprehension or worry regarding social situations and being evaluated by others. ... This does not adequately cite its references or sources. ... This article does not cite any references or sources. ... In psychology, anhedonia is a patients inability to experience pleasure from normally pleasurable life events such as eating, exercise, and social/sexual interactions. ... For the classical mythological figures named Mania, see Mania (mythology). ... Hypersexuality describes human sexual behavior at levels high enough to be considered clinically significant. ...


Salience

Dopamine may also have a role in the salience ('noticeableness') of perceived objects and events, with potentially important stimuli such as: 1) rewarding things or 2) dangerous or threatening things seeming more noticeable or important.[12] This hypothesis argues that dopamine assists decision-making by influencing the priority, or level of desire, of such stimuli to the person concerned. The salience (also called saliency) of an item is its state or quality of standing out relative to other items. ...


Behavior disorders

Pharmacological blockade of brain dopamine receptors increases rather than decreases drug-taking behaviour. Since blocking dopamine decreases desire, the increase in drug-taking behaviour may be seen as not a chemical desire but as a deeply psychological desire to just 'feel something'.


Deficits in dopamine levels are implicated in Attention-deficit hyperactivity disorder (ADHD), and stimulant medications used to successfully treat the disorder increase dopamine neurotransmitter levels, leading to decreased symptoms. Attention-Deficit/Hyperactivity Disorder (ADHD) previously known as Attention Deficit Disorder (ADD), is generally considered to be a developmental disorder, largely neurological in nature, affecting about 5% of the worlds population. ...


Latent inhibition and creative drive

Dopamine in the mesolimbic pathway increases general arousal and goal directed behaviors and decreases latent inhibition; all three effects increase the creative drive of idea generation. This has led to a three-factor model of creativity involving the frontal lobes, the temporal lobes, and mesolimbic dopamine.[13] The mesolimbic pathway is one of the neural pathways in the brain that link the ventral tegmentum in the midbrain to the nucleus accumbens in the limbic system. ... Arousal is a physiological and psychological state of being awake. ... Latent inhibition is inhibition of the learning of a paired association between a conditioned stimulus and unconditioned stimulus due to prior repeated unpaired exposure of the conditioned stimulus. ... For other uses of Creativity, see Creativity (disambiguation). ... The frontal lobe is an area in the brain of mammals. ... The temporal lobes are part of the cerebrum. ...


Links to psychosis

Disruption to the dopamine system has also been strongly linked to psychosis and schizophrenia,[14] with abnormally high dopamine action apparently leading to these conditions. Dopamine neurons in the mesolimbic pathway are particularly associated with these conditions. Evidence comes partly from the discovery of a class of drugs called the phenothiazines (which block D2 dopamine receptors) that can reduce psychotic symptoms, and partly from the finding that drugs such as amphetamine and cocaine (which are known to greatly increase dopamine levels) can cause psychosis.[15] Because of this, most modern antipsychotic medications, for example, Risperidone, are designed to block dopamine function to varying degrees. The dopamine hypothesis of schizophrenia or the dopamine hypothesis of psychosis is a theory that argues that the unusual behaviour and experiences associated with schizophrenia (sometimes extended to psychosis in general) can be fully or largely explained by changes in dopamine function in the brain. ... Psychosis is a generic psychiatric term for a mental state often described as involving a loss of contact with reality. Stedmans Medical Dictionary defines psychosis as a severe mental disorder, with or without organic damage, characterized by derangement of personality and loss of contact with reality and causing deterioration... The mesolimbic pathway is one of the neural pathways in the brain that link the ventral tegmentum in the midbrain to the nucleus accumbens in the limbic system. ... Phenothiazines are the largest of the 5 main classes of antipsychotic drugs. ... The dopamine receptors are a class of metabotropic G-protein-coupled receptors with the neurotransmitter dopamine as their endogenous ligand. ... Amphetamine or Amfetamine(Alpha-Methyl-PHenEThylAMINE), also known as beta-phenyl-isopropylamine and benzedrine, is a prescription stimulant commonly used to treat Attention-deficit hyperactivity disorder (ADHD) in adults and children. ... Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. ... The term antipsychotic is applied to a group of drugs used to treat psychosis. ... Risperdal tablets Risperidone (pronounced Ris-PER-ǐ-dōn and sold under the trade name Risperdal in the United States, Canada, the United Kingdom, Portugal and several other countries, Risperdal or Ridal in New Zealand, Rispolept in Eastern Europe, and Belivon, or Rispen elsewhere) is an atypical antipsychotic medication developed by...


Therapeutic use

Main article: L-DOPA

Levodopa is a dopamine precursor used in various forms to treat Parkinson's disease. It is typically co-administered with an inhibitor of peripheral decarboxylation (DDC, dopa decarboxylase), such as carbidopa or benserazide. Inhibitors of alternative metabolic route for dopamine by catechol-O-methyl transferase are also used. These include entacapone and tolcapone. // Therapeutic use L-DOPA is used to replace dopamine lost in Parkinsons disease because dopamine itself cannot cross the blood-brain barrierwhere its precursor can. ... // Therapeutic use L-DOPA is used to replace dopamine lost in Parkinsons disease because dopamine itself cannot cross the blood-brain barrierwhere its precursor can. ... Aromatic-L-amino-acid decarboxylase (EC 4. ... Carbidopa (MK-486) is a drug given to people with Parkinsons disease in order to inhibit peripheral metabolism of levodopa. ... Benserazide is an inhibitor of DOPA decarboxylase that does not enter the central nervous system. ... Catechol-O-methyl transferase (COMT) (EC 2. ... Cant give you an article unless I copy my pharmacists notes, but the common name for ENTACAPONE is COMTAN, at least that is the name NOVARTIS uses. ... Tolcapone, an inhibitor of catechol-O-methyltransferase (COMT), is used in the treatment of Parkinson’s disease as an adjunct to levodopa/carbidopa therapy. ...


Dopamine is also used as an inotropic drug in patients with shock to increase cardiac output and blood pressure. An inotrope is an agent which increases or decreases the force or energy of muscular contractions. ... This article is about the medical condition. ... Cardiac output (CO) is the volume of blood being pumped by the heart, in particular by a ventricle in a minute. ... A sphygmomanometer, a device used for measuring arterial pressure. ...


Major pathways

The mesocortical pathway is a neural pathway which connects the ventral tegmentum to the cortex, particularly the frontal lobes. ... The mesolimbic pathway is one of the neural pathways in the brain that link the ventral tegmentum in the midbrain to the nucleus accumbens in the limbic system. ... The nigrostriatal pathway is a neural pathway which connects the substantia nigra with the striatum. ... The tuberoinfundibular pathway is a neural pathway which runs between the hypothalamus and the pituitary gland. ...

Dopamine and fruit browning

Polyphenol oxidases (PPOs) are a family of enzymes responsible for the browning of fresh fruits and vegetables when they are cut or bruised. These enzymes use molecular oxygen (O2) to oxidise various 1,2-diphenols to their corresponding quinones. The natural substrate for PPOs in bananas is dopamine. The product of their oxidation, dopamine quinone, spontaneously oxidises to other quinones. The quinones then polymerise and condense with amino acids and proteins to form brown pigments known as melanins. The quinones and melanins derived from dopamine may help protect damaged fruit and vegetables against growth of bacteria and fungi.[16] Polyphenol oxidase (PPO) enzymes catalyse the o-hydroxylation of monophenols (phenol molecules in which the benzene ring contains a single hydroxyl substituent) to o-diphenols (phenol molecules containing two hydroxyl substituents). ... Browning is the process of becoming brown, especially refering to food. ... General Name, symbol, number oxygen, O, 8 Chemical series nonmetals, chalcogens Group, period, block 16, 2, p Appearance colorless (gas) pale blue (liquid) Standard atomic weight 15. ... ed|other uses|reduction}} Illustration of a redox reaction Redox (shorthand for reduction/oxidation reaction) describes all chemical reactions in which atoms have their oxidation number (oxidation state) changed. ... Benzenediols or dihydroxybenzenes are aromatic chemical compounds in which two hydroxyl groups are substituted onto a benzene ring. ... A quinone (or benzoquinone) is either one of the two isomers of cyclohexadienedione or a derivative thereof. ... This article or section does not cite its references or sources. ... Polymerization is the formation of long, repeating organic polymer chains. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... This article is about the class of chemicals. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... The Blue Morpho butterfly, native to Central America, derives its distinctive blue coloring from iridescence rather than from pigmentation. ... Broadly, melanin is any of the polyacetylene, polyaniline, and polypyrrole blacks and browns or their mixed copolymers. ...


References

  1. ^ Benes, F.M. Carlsson and the discovery of dopamine. Trends in Pharmacological Sciences, Volume 22, Issue 1, 1 January 2001, Pages 46-47.
  2. ^ Schultz, Cambridge university, UK
  3. ^ Barron AB, Maleszka R, Vander Meer RK, Robinson GE (2007). "Octopamine modulates honey bee dance behavior". Proc. Natl. Acad. Sci. U.S.A. 104 (5): 1703-7. doi:10.1073/pnas.0610506104. PMID 17237217. 
  4. ^ Giuliano, F.; Allard J. (2001). "Dopamine and male sexual function". Eur Urol 40: 601-608. PMID 11805404. 
  5. ^ Giuliano, F.; Allard J. (2001). "Dopamine and sexual function". Int J Impot Res 13 (Suppl 3): S18-S28. doi:10.1038/sj.ijir.3900719. PMID 11477488. 
  6. ^ Berridge K, Robinson T (1998). "What is the role of dopamine in reward: hedonic impact, reward learning, or incentive salience?". Brain Res Brain Res Rev 28 (3): 309-69. PMID 9858756. 
  7. ^ Peciña S, Cagniard B, Berridge K, Aldridge J, Zhuang X (2003). "Hyperdopaminergic mutant mice have higher "wanting" but not "liking" for sweet rewards.". J Neurosci 23 (28): 9395-402. PMID 14561867. 
  8. ^ Lambert M, Schimmelmann B, Karow A, Naber D (2003). "Subjective well-being and initial dysphoric reaction under antipsychotic drugs - concepts, measurement and clinical relevance.". Pharmacopsychiatry 36 (Suppl 3): S181-90. PMID 14677077. 
  9. ^ Lemke M, Brecht H, Koester J, Kraus P, Reichmann H (2005). "Anhedonia, depression, and motor functioning in Parkinson's disease during treatment with pramipexole.". J Neuropsychiatry Clin Neurosci 17 (2): 214-20. PMID 15939976. 
  10. ^ Peciña S, Berridge K (2005). "Hedonic hot spot in nucleus accumbens shell: where do mu-opioids cause increased hedonic impact of sweetness?". J Neurosci 25 (50): 11777-86. PMID 16354936. 
  11. ^ Pfaus J, Phillips A (1991). "Role of dopamine in anticipatory and consummatory aspects of sexual behavior in the male rat.". Behav Neurosci 105 (5): 727-43. PMID 1840012. 
  12. ^ Schultz W (2002). "Getting formal with dopamine and reward". Neuron 36 (2): 241-263. PMID 12383780. 
  13. ^ Flaherty, A.W, (2005). "Frontotemporal and dopaminergic control of idea generation and creative drive". Journal of Comparative Neurology 493 (1): 147-153. PMID 16254989. 
  14. ^ Disruption of gene interaction linked to schizophrenia. St. Jude Children's Research Hospital. Retrieved on 2006-07-06.
  15. ^ Lieberman, J.A.; JM Kane, J. Alvir (1997). "Provocative tests with psychostimulant drugs in schizophrenia.". Psychopharmacology (Berl). 91 (4): 415-433. PMID 2884687. Retrieved on 2007-10-16. 
  16. ^ Mayer, AM (2006). "Polyphenol oxidases in plants and fungi: Going places? A review". Phytochemistry 67: 2318-2331. PMID 16973188. 

A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 187th day of the year (188th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 289th day of the year (290th in leap years) in the Gregorian calendar. ...

See also

Heroin bottle An addiction is a recurring compulsion by an individual to engage in some specific activity, despite harmful consequences to the individuals health, mental state or social life. ... Amphetamine or Amfetamine(Alpha-Methyl-PHenEThylAMINE), also known as beta-phenyl-isopropylamine and benzedrine, is a prescription stimulant commonly used to treat Attention-deficit hyperactivity disorder (ADHD) in adults and children. ... The term antipsychotic is applied to a group of drugs used to treat psychosis. ... tyrosine is the precursor of catecholamines epinephrine norepinephrine dopamine Synthesis Catecholamines are chemical compounds derived from the amino acid tyrosine containing catechol and amine groups. ... Catechol-O-methyl transferase (COMT) (EC 2. ... It has been suggested that eye blink conditioning be merged into this article or section. ... Operant conditioning is the use of consequences to modify the occurrence and form of behavior. ... Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. ... The dopamine hypothesis of schizophrenia or the dopamine hypothesis of psychosis is a theory that argues that the unusual behaviour and experiences associated with schizophrenia (sometimes extended to psychosis in general) can be fully or largely explained by changes in dopamine function in the brain. ... This does not cite any references or sources. ... Vitamin R redirects here. ... Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ... A prolactinoma is a benign tumor (adenoma) of the pituitary gland that produces a hormone called prolactin. ... Selegiline (l-deprenyl, Eldepryl® or Anipryl® [veterinary]) is a drug used for the treatment of early-stage Parkinsons disease and senile dementia. ...

External links

Look up Dopamine in Wiktionary, the free dictionary.

  Results from FactBites:
 
Dopamine (335 words)
During the last stages of evolution in mammals, the characteristic extension of dopamine cortical innervation is also correlated with the development of cognitive capacities.
For example, in Parkinson's disease, besides motor impairment, dopamine degeneration is also expressed by alterations of both limbic, executive and cognitive functions, both improved by dopamine receptor agonists and dopa therapy.
Dopamine has thus to be considered as a key regulator that contributes to behavioural adaptation and to the anticipatory processes necessary for preparing voluntary action consequent upon intention.
Dopamine definition - Medical Dictionary definitions of popular medical terms (284 words)
Dopamine is classified as a catecholamine (a class of molecules that serve as neurotransmitters and hormones).
Dopamine is a precursor (forerunner) of adrenaline and a closely related molecule, noradrenaline.
Dopamine is formed by the decarboxylation (removal of a carboxyl group) from dopa.
  More results at FactBites »

 
 

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