GABAB heterodimeric receptor binds GABA

Gamma-aminobutyric acid (GABA) is the chief inhibitory neurotransmitter in the mammalian central nervous system. GABA exerts its effects through two ligand-gated channels and a the GPCR GABAB (Kaupmann K et al, 1998), which acts through G proteins to regulate potassium and calcium channels. GABAB can only bind GABA once it forms a heterodimer composed of the GABABR1 and GABABR2 receptors (White JH et al, 1998). The effects of this dimer are mediated by coupling to the G protein alpha i subunit, which inhibits adenylyl cyclase (Odagaki & Koyama 2001).

γ-氨基丁酸（GABA）是哺乳动物中枢神经系统中主要的抑制性神经递质。GABA通过两种配体门控通道以及G蛋白偶联受体GABAB（Kaupmann K 等人，1998年）发挥作用，后者通过G蛋白调控钾和钙通道。GABAB仅能在GABABR1和GABABR2受体组成的异源二聚体形成后与GABA结合（White JH 等人，1998年）。此二聚体的作用通过与其G蛋白αi亚单位的偶联而介导，该亚单位抑制腺苷酸环化酶（Odagaki & Koyama 2001年）。