演題詳細
Poster
ラット三叉神経節およびSp5C におけるGABAB 受容体とKCTD蛋白の発現および相互作用
Expression and interaction of GABAB receptors and KCTD proteins in rat trigeminal ganglion and spinal trigeminal nucleus caudalis
- P3-160
- 早﨑 華 / Hana Hayasaki:1 相馬 義郎 / Yoshiro Sohma:2 大槻 勝紀 / Yoshinori Otsuki:3
- 1:関西福祉科学大学 / Kansai University of Welfare Sciences 2:慶應義塾大学 薬理学教室 / Department of Pharmacology and Neuroscience, School of Medicine, Keio University 3:大阪医科大学 解剖学教室 / Department of anatomy, Osaka medical college
GABAB receptor is a G-protein-coupled receptor for γ-aminobutyric acid (GABA), the main inhibitory neurotransmitter. The GABAB receptors are formed with GABABR1 and GABABR2 subunits or GABABR2 only and are expressed in almost all neurons in brain. KCTD proteins are auxiliary subunits of GABAB receptors that affect the pharmacological characteristics and the kinetics of the receptor response. Previously we found heterogeneous expressions of GABABR1 and GABABR2 subunits and auxiliary subunits KCTD12 and KCTD16 in the rat trigeminal ganglion (TG). In this study, we investigated distributions and interactions of GABABR1, GABABR2, KCTD12 and KCTD16 in TG and brainstem using co-immunoprecipitation assay and immnohistohemistry.
In Western blotting, GABABR1, GABABR2 and KCTD12, but not KCTD16, were detected in rat TG membrane fraction whereas all of them were detected in cytosolic fraction of TG and in both cytosol and membrane fractions of brainstem. Co-immunoprecipitation assay suggested that GABABR1 and/or GABABR2, and KCTD12 and/or KCTD16 formed a complex in TG and brainstem whereas there was no complex involving both GABABR1 and KCTD16 in TG.
In spinal trigeminal nucleus caudalis (Sp5C) of brain stem, all GABABR1, GABABR2, KCTD12, and KCTD16 were detected in neuropil and neuronal bodies by immunohistchemical staining.
These results suggest that GABAB receptors form complexes with KCTD12 and/or KCTD16 in TG and brainstem whereas the complexes involved GABABR1 or KCTD16 alternatively in TG.