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多巴胺受體D2
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功能
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D2R属于一种多巴胺受体，并会与Gᵢ结合。Gᵢ为G蛋白偶联受体的一种亚型，会抑制腺苷酸环化酶的活性。_NEWLINE_在小鼠模式中，齿状回的neuronal calcium sensor-1（NCS-1）会影响D2R在细胞膜的表现量。这项机制会影响突触可塑性及记忆形成。_NEWLINE_在苍蝇模式中，多巴胺性神经元上的D2R自体受器能避免神经元死亡，进而引发类帕金森病的症状。
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同型体
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Alternative splicing of this gene results in three transcript variants encoding different isoforms._NEWLINE_The long form (D2Lh) has the "canonical" sequence and functions as a classic post-synaptic receptor.The short form (D2Sh) is pre-synaptic and functions as an autoreceptor that regulates the levels of dopamine in the synaptic cleft.Agonism of D2sh receptors inhibits dopamine release; antagonism increases dopaminergic release.A third D2(Longer) form differs from the canonical sequence where 270V is replaced by VVQ.
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配体
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Most of the older antipsychotic drugs such as chlorpromazine and haloperidol are antagonists for the dopamine D₂ receptor, but are, in general, very unselective, at best selective only for the "D₂-like family" receptors and so binding to D₂, D₃ and D₄, 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 D₂ agonists, they affect other subtypes as well. Several selective D₂ ligands are, however, now available, and this number is likely to increase as further research progresses.
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Protein–protein interactions
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The dopamine receptor D₂ has been shown to interact with EPB41L1,PPP1R9Band NCS-1.