多巴胺受體D二

多巴胺受體 D 二（Dopamine receptor D 二，簡稱D 二 R）， 為著轉譯自 _ DRD 二 _ 基因的一種多巴胺受體卵白。D 二 R 上早佇一九七五年為 Philip Seeman 所發現講，並共號名做「抗精神疾患性多巴胺受體」（_ antipsychotic dopamine receptor _）。 D 二 R 為所有抗精神病藥物的作用標的。

功能

D 二 R 屬於一種多巴胺受體，並會佮 Gi 結合。Gi 為 G 卵白尪仔聯受體的一種亞型，會壓制腺酸環化扣的活性。

佇鳥鼠仔模式當中，齒型的轉來 neuronal calcium sensor 影一（NCS 影一）會影響 D 二 R 佇細胞膜的表現量。這項機制會影響雄雄有塑性佮記持形成。

佇胡蠅模式內底，多巴胺性神經元上的 D 二 R 自體受器能避免神經元死亡，進一步引發類帕金森症的症頭。

仝型體

Alternative splicing of this gene results in three transcript variants encoding different isoforms .

The long form (D 二 Lh) has the " canonical " sequence and functions as a classic post-synaptic receptor . The short form (D 二 Sh) is pre-synaptic and functions as an autoreceptor that regulates the levels of dopamine in the synaptic cleft . Agonism of D 二 sh receptors inhibits dopamine release ; antagonism increases dopaminergic release . A third D 二 ( Longer ) form differs from the canonical sequence where 兩百七十 V is replaced by VVQ .

基因組

等位基因變化：

• A 抹兩百四十一 G
• C 一百三十二 T、G 四仔二三 A、T 七仔六十五 C、C 九百三十九 T、C 九百五十七 T，以及 G 一千一百空一 A
• Cys 三百十一 Ser
• 抹一百四十一 C insertion / deletionThe polymorphisms have been investigated with respect to association with schizophrenia .

Some researchers have previously associated the polymorphism Taq 一 A ( rs 一百八十五空四百九十七 ) to the _ DRD 二 _ gene . However , the polymorphism resides in exon 八 of the _ ANKK 一 _ gene . DRD 二 TaqIA polymorphism has been reported to be associated with an increased risk for developing motor fluctuations but not hallucinations in Parkinson's disease .

配體

Most of the older antipsychotic drugs such as chlorpromazine and haloperidol are antagonists for the dopamine D 二 receptor , but are , in general , very unselective , at best selective only for the " D 二-like family " receptors and so binding to D 二 , D 三 and D 四 , and often also to many other receptors such as those for serotonin and histamine , resulting in a range of side-effects and making them poor agents for scientific research . In similar manner , older dopamine agonists used for Parkinson's disease such as bromocriptine and cabergoline are poorly selective for one dopamine receptor over another , and , although most of these agents do act as D 二 agonists , they affect other subtypes as well . Several selective D 二 ligands are , however , now available , and this number is likely to increase as further research progresses .

Functionally selective ligands

• 參見參考文獻。

Protein–protein interactions

The dopamine receptor D 二 has been shown to interact with EPB 四十一 L 一 , PPP 一 R 九 Band NCS 影一 .

Receptor oligomers

The D 二 receptor forms receptor heterodimers _ in vivo _ ( in living animals ) with other G protein-coupled receptors ; these include :

• D 一–D 二 dopamine receptor heteromer
• D 二–adenosine A 二 A
• D 二–ghrelin receptor
• D 二 sh–TAAR 一

The D 二 receptor has been shown to form hetorodimers _ in vitro _ ( and possibly _ in vivo _ ) with DRD 三 , DRD 五 , and 五-HT 二 A .

外部連結

• 醫學主題詞表（MeSH）： _ Receptors , + Dopamine + D 二 _
• Pappas , Stephanie . Study : Genes Influence Who Your Friends Are . Imaginova Corp . LiveScience . [二十 January 二千空一十一] .

多巴胺受體 D 二引用美國國家醫學圖書館提供的資料，遮的資料屬於公共領域。

Template : Dopaminergics