一般ポスター

一般ポスター神経伝達物質・受容体-1

7月6日（木）　13:20-14:20　ポスター会場① 1P①-1 The mechanism regulating localization of G protein-coupled receptors to primary cilia in hTERT-RPE1 cells 三好　耕^1,2, 秦　圓圓¹, 藤原　悠紀¹, 吉村　武¹, 片山　泰一¹ 1. 大阪大院　連合小児発達　分子生物遺伝, 2. 大阪大院　連合小児発達　子どものこころ Ko Miyoshi^1,2, Yuanyuan Qin¹, Yuuki Fujiwara¹, Takeshi Yoshimura¹, Taiichi Katayama¹ 1. Dept. of Child Develop. and Molecular Bra. Sci., United Grad. Sch. of Child Develop., Osaka Univ., Suita, Japan Almost all vertebrate cells have an immotile primary cilium that singly extends like an antenna and transduces sensory stimuli to the cell body. In the rodent brain each neuron has a solitary primary cilium for nearly all regions. The neuronal primary cilium is thought to be a non-synaptic neurotransmission device, while its exact nature is poorly understood. In humans, functional disruption of primary cilia results in a spectrum of pleiotropic disorders, referred to as ciliopathies. Adenylyl cyclase 3 and several G protein-coupled receptors (GPCRs) have been found to be localized in primary cilia of neuronal cells in rodents, and it might then be possible that a G protein/cAMP signaling cascade in neuronal primary cilia transduces the extracellular stimuli to the neuronal cell body. In this study, we analyzed ciliary localization of several GPCRs and their variants in cultured hTERT-RPE1 cells to determine the possible domain that targets GPCRs to the ciliary compartment. We also examined ciliary localization of several GPCRs in hTERT-RPE1 cells carrying biallelic genomic mutations that disrupt genes known to be responsible for ciliopathies. The present study provides some insight into the possible mechanism by which several GPCRs can be selectively localized to primary cilia and the association of the ciliary localization of GPCRs with ciliopathies.		7月6日（木）　13:20-14:20　ポスター会場① 1P①-2 The molecular mechanism by which serotonin receptor type 6 localizes to primary cilia 秦　圓圓, 三好　耕, 銀生　卓瑪, 藤原　悠紀, 吉村　武, 片山　泰一大阪大院　連合小児発達　分子生物遺伝 Yuanyuan Qin, Ko Miyoshi, Zhuoma Yinsheng, Yuuki Fujiwara, Takeshi Yoshimura, Taiichi Katayama Dept. of Child Develop. and Molecular Bra. Sci., United Grad. Sch. of Child Develop., Osaka Univ., Suita, Japan In the brain, nearly all neurons have a single primary cilium, a cell's antenna. Most G protein-coupled receptors (GPCRs) localize to the cell surface, while a subset of GPCRs including serotonin receptor type 6 (Htr6) localize specifically to primary cilia. Interestingly, it has been demonstrated that neurotransmission occurs via synapses between serotonergic axons and primary cilia expressing Htr6, thereby regulating epigenetic states of the postsynaptic neurons. In this study, we aimed to identify molecule(s) that interact with Htr6 and determine cilia localization of Htr6. The fourth intracellular domain (i4) of Htr6 fused to CD8α localized to primary cilia in hTERT-RPE1 (RPE1) cells, suggesting that localization of Htr6 to primary cilia depends on its i4. Then, we searched interactors of Htr6-i4 by yeast two-hybrid screening, identifying several molecules as candidate interactors. Immunoprecipitation analysis in HEK293T cells verified interaction of Htr6-i4 with one of the candidates, Factor X. Ciliary localization of Htr6 and CD8α-Htr6-i4 was downregulated in Factor X-knockout RPE1 cells we established. Our results indicate that interaction of Factor X with Htr6-i4 is likely to mediate ciliary localization of Htr6 in RPE1 cells.

7月6日（木）　13:20-14:20　ポスター会場① 1P①-3 Cooperative effect of GABA and Ca2+ for the diffusion and trapping of GABAARs at synapses: regulation of receptor number 丹羽　史尋^1,2 1. 自治医科大学, 2. Institut de Biologie, Ecole Normale Superieure, PSL Research University, INSERM U1024 Fumihiro Niwa^1,2 1. Jichi Medical University, 2. Institut de Biologie, Ecole Normale Superieure, PSL Research University, INSERM U1024 The receptor number at synapses determines the efficiency of neurotransmission. Thus, mechanisms regulating GABA_AR diffusion and synaptic trapping are crucial for tuning GABAergic transmission. Bindings of agonists to GABA_AR and its post-translational modification modify its trapping at synapses. However, the cooperation of pre-and post-synaptic activity for the regulation of the diffusion-trapping of GABA_AR is poorly understood due to the technical difficulty to separate the effect of presynaptic GABA release and post-synaptic Ca²⁺ elevation. To solve this problem, we tackled single-molecule-localization-microscopy of GABA_AR using spontaneously blinking dye in combination with GABA uncaging and optogenetics. We found in mature synapses (> 21 days in vitro) from cultured dissociated neurons that repetitive GABA uncaging combined with simultaneous Ca²⁺ elevation induced a rapid and persistent reduction of GABA_ARγ2-subunit-containing receptors from the stimulated synapse. Neither sole Ca²⁺-elevation nor GABA-uncaging alone couldn’t induce this phenomenon. Thus, both the binding of GABA which induce dissociation of GABA_ARs from scaffolds combined with neuronal activity and Ca²⁺ elevation prevent re-accumulation of receptors to synaptic sites could be indispensable for the long-lasting loss of GABA_ARs from synapses and a subsequent dis-inhibition.		7月6日（木）　13:20-14:20　ポスター会場① 1P①-4 マウス脳虚血再灌流障害に対するNMDA前投与の神経保護効果 Neuroprotective effects of pretreatment of NMDA against cerebral ischemia-reperfusion injury in mice 米山　雅紀, 山口　太郎, 尾中　勇祐摂南大学　薬学部　薬理学 Masanori Yoneyama, Taro Yamaguchi, Yusuke Onaka Lab. of Pharmacol., Fac. of Pharmaceu. Sci., Setsunan Uni., Osaka, Japan Activation of N-methyl-D-aspartate (NMDA) receptors has been shown to induce either neuronal cell death or neuroprotection against excitotoxicity in cultured neurons in vitro. To elucidate in vivo neuroprotective role of NMDA receptors, we investigated the effects of pretreatment of NMDA on cerebral ischemia-reperfusion injury to the mouse brain in vivo. Middle cerebral artery occlusion (MCAO) was performed to induce cerebral ischemia-reperfusion injury in mice 24 h after the administration of NMDA (100 mig/kg, i. p.). Cerebral ischemic volume was measured by TTC staining. Zea longa score was used to evaluate neurological deficits in mice. The prior administration of NMDA at 24 h before significantly prevented cerebral infraction area by MCAO. In addition, neurological symptom score at 24 h after MCAO was markedly decrease by pretreatment of NMDA. These results suggest that in vivo treatment with NMDA is capable of protecting against MCAO-induced cerebral ischemia-reperfusion injury.

7月6日（木）　13:20-14:20　ポスター会場① 1P①-5 海馬背部protein targeting to glycogenのグルタミン酸受容体発現調節を介したマウスの短期記憶への寄与 The dorsal hippocampal protein targeting to glycogen contributes to short-term memory via glutamate receptor expression 神戸　悠輝鹿児島大学　医歯学総合研究科　生体情報薬理学 Yuki Kambe Department of Pharmacology, Graduate School of Medical and Dental Science, Kagoshima University Brain glycogen metabolism is known to be involved in the learning and memory processes. Protein targeting to glycogen (PTG) is a crucial molecule for glycogenesis. Its expression level is shown to be increased in the dorsal hippocampus during fear memory acquisition and recall, suggesting that PTG may contribute to the memory process. However, its detailed role in the dorsal hippocampus remains unclear. Therefore, we knocked down the expression of PTG in the dorsal hippocampus and attempted to analyze its function behaviorally. PTG expression was found to be enriched in astrocytes.Furthermore, short hairpin RNA against PTG suppressed the expression of PTG in astrocytes. Mice with knockdown of PTG in the dorsal hippocampus showed hidden alternation behavior in the Y-maze test and reduced memory recalls in the first hour after acquisition in the passive avoidance test. Knockdown of mouse dorsal hippocampal astrocyte-specific PTG also impaired working memory in the Y-maze test. GluR1, GluR2, and NR2a subunits expressions were significantly down-regulated in the dorsal hippocampus of mice where PTG was knocked down. These results indicate that PTG in the dorsal hippocampal astrocytes may contribute to working and short-term memories by maintaining the expression of glutamate receptor subunits.		7月6日（木）　13:20-14:20　ポスター会場① 1P①-6 オピオイド受容体拮抗薬のマウス動機付け行動および脳モノアミン代謝回転への影響 Effects of opioid receptor antagonists on motivative behavior and brain monoamine turnover in mice 北中　純一¹, 北中　順惠², 富田　和男³, 五十嵐　健人³, 荒井　香奈代², 竹原　薫生子², 濱名　貴大¹, 松田　健太郎¹, 仲井　聖典¹, 湯瀬　祥¹, 佐藤　友昭³ 1. 兵庫医科大学　薬学部　医療薬学科　薬物中毒治療, 2. 兵庫医科大学　医学部　薬理, 3. 鹿児島大学大学院　医歯学総合研究科　歯科応用薬理学分野 Junichi Kitanaka¹, Nobue Kitanaka², Kazuo Tomita³, Kento Igarashi³, Kanayo Arai², Kaoko Takehara², Takahiro Hamana¹, Kentaro Matsuda¹, Masanori Nakai¹, Sho Yuze¹, Tomoaki Sato³ 1. Lab. Drug Addict. Exp. Ther., Sch. Pharm., Hyogo Med. Univ., Kobe, Hyogo, Japan, 2. Dept. Pharmacol., Sch. Med., Hyogo Med. Univ., 3. Dept. Appl. Pharmacol., Grad. Sch Med. & Dent., Kagoshima Univ. It is hypothesized that μ-opioid receptor antagonists could inhibit the natural reward as well as drug addiction such as opioids and stimulants. To evaluate natural reward, horizontal running wheels were applied to mice administered with a selective μ-opioid receptor antagonist β-funaltrexamine (β-FNA). In naive mice, horizontal locomotion increased day by day for three testing days. The increment was parallel to the increase in the rotation of running wheels but not to the number of accesses to food containers. The increase in the rotation of running wheels was sensitized, and the amount of food intake was unchanged in naive mice. In mice group which was administered with a single injection of 5 mg/kg β-FNA, rotation of the running wheels and the locomotion decreased especially in the first testing day. In contrast, no significant behavioral change was observed in mice under a continuous s.c. administration with osmotic mini-pumps (3.5 mg /kg of β-FNA for three days (71.5 h)). No alterations in monoamine turnovers in the cerebral cortex and the region of the striatum and nucleus accumbens were observed. These results indicate that a transient increase in the levels of β-FNA reduced motivative behaviors via mechanism not related to brain monoamine turnover in mice.