Dopamine: Difference between revisions

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imported>Robert Badgett
(New article)
 
imported>Robert Badgett
(Started 'Clinical pharmacology')
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Agonists of D3, especially nonergot agonists such as pramipexole and ropinirole, may be used to treat [[Parkinonism]] and restless legs syndrome.<ref name="pmid18474889">{{cite journal |author=Baker WL, White CM, Coleman CI |title=Effect of nonergot dopamine agonists on symptoms of restless legs syndrome |journal=Ann Fam Med |volume=6 |issue=3 |pages=253–62 |year=2008 |pmid=18474889 |doi=10.1370/afm.845 |url=http://www.annfammed.org/cgi/pmidlookup?view=long&pmid=18474889 |issn=}}</ref>
Agonists of D3, especially nonergot agonists such as pramipexole and ropinirole, may be used to treat [[Parkinonism]] and restless legs syndrome.<ref name="pmid18474889">{{cite journal |author=Baker WL, White CM, Coleman CI |title=Effect of nonergot dopamine agonists on symptoms of restless legs syndrome |journal=Ann Fam Med |volume=6 |issue=3 |pages=253–62 |year=2008 |pmid=18474889 |doi=10.1370/afm.845 |url=http://www.annfammed.org/cgi/pmidlookup?view=long&pmid=18474889 |issn=}}</ref>
;D4 receptors
;D4 receptors
==Clinical pharmacology==
===Dopamine agonists===
Dopamine agonists are "dugs that bind to and activate dopamine receptors."<ref name="MeSH-DopamineAgonists">{{MeSH|Dopamine agonists}}</ref>
===Dopamine antagonists===
Dopamine antagonists are "drugs that bind to but do not activate dopamine receptors, thereby blocking the actions of dopamine or exogenous agonists. Many drugs used in the treatment of psychotic disorders ([[antipsychotic agent]]s) are dopamine antagonists, although their therapeutic effects may be due to long-term adjustments of the brain rather than to the acute effects of blocking dopamine receptors. Dopamine antagonists have been used for several other clinical purposes including as [[antiemetic]]s, in the treatment of [[Tourette syndrome]], and for [[hiccup]]. Dopamine receptor blockade is associated with [[neuroleptic malignant syndrome]]."<ref name="MeSH-DopamineAntagonists">{{MeSH|Dopamine antagonists}}</ref>


==References==
==References==
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Revision as of 06:40, 9 September 2009

Dopamine is "one of the catecholamine neurotransmitters in the brain. It is derived from tyrosine and is the precursor to norepinephrine and epinephrine. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (dopamine receptors) mediate its action."[1]

Dopamine regulates the secretion of prolactin from the anterior pituitary gland. Dopamine is released from specialised neurons of the arcuate nucleus of the hypothalamus into the blood vessels of the median eminence, which transport the dopamine to the pituitary gland where it inhibits prolactin secretion from lactotroph cells.

Dopamine receptors

D1-like receptors

These receptors stimulate adenylate cyclase.[2]

D1 receptors
D5 receptors

D2-like receptors

These receptors inhibit adenylate cyclase.[3]

Dopamine D2 receptors

Agonists, such as metoclopramide, are used as antiemetics.

Antagonists, such as risperidone and haloperidol, are used to treat schizophrenia.[4]

Blockade of the D2 receptors, which may be predisposed by genetic polymorphisms of the allele, may cause neuroleptic malignant syndrome.[5]

D3 receptors

Agonists of D3, especially nonergot agonists such as pramipexole and ropinirole, may be used to treat Parkinonism and restless legs syndrome.[6]

D4 receptors

Clinical pharmacology

Dopamine agonists

Dopamine agonists are "dugs that bind to and activate dopamine receptors."[7]

Dopamine antagonists

Dopamine antagonists are "drugs that bind to but do not activate dopamine receptors, thereby blocking the actions of dopamine or exogenous agonists. Many drugs used in the treatment of psychotic disorders (antipsychotic agents) are dopamine antagonists, although their therapeutic effects may be due to long-term adjustments of the brain rather than to the acute effects of blocking dopamine receptors. Dopamine antagonists have been used for several other clinical purposes including as antiemetics, in the treatment of Tourette syndrome, and for hiccup. Dopamine receptor blockade is associated with neuroleptic malignant syndrome."[8]

References