演題詳細
Oral
視覚 2
Visual System 2
開催日 | 2014/9/11 |
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時間 | 17:00 - 18:00 |
会場 | Room G(303) |
Chairperson(s) | 七五三木 聡 / Satoshi Shimegi (大阪大学大学院医学系研究科 / Graduate School of Medecine, Osaka University, Japan) 小松 英彦 / Hidehiko Komatsu (自然科学研究機構 生理学研究所 / National Institute for Physiological Sciences, Japan) |
マウス大脳皮質視覚野におけるGABA作動性ニューロンクラスターの機能的意義
Functional significance of GABAergic interneuron clusters in the three-dimensional space of the mouse visual cortex
- O1-G-2-1
- 蝦名 鉄平 / Teppei Ebina:1 惣谷 和広 / Kazuhiro Sohya:1 今吉 格 / Itaru Imayoshi:2 Yin Shu-Ting / Shu-Ting Yin:1 木村 塁 / Rui Kimura:1 柳川 右千夫 / Yuchio Yanagawa:3 亀田 浩司 / Hiroshi Kameda:4 日置 寛之 / Hiroyuki Hioki:4 金子 武嗣 / Takeshi Kaneko:4 津本 忠治 / Tadaharu Tsumoto:1
- 1:理化学研究所 BSI / Brain Science Inst., RIKEN, Wako, Japan 2:京都大学 白眉センター・ウイルス研究所 / The Hakubi Center, Institute for Virus Research, Kyoto University, Kyoto, Japan 3:群馬大学大学院 医学系研究科 脳神経発達統御学講座 / Neurobiology and Behavior, Graduate School of Medicine, Gunma University, Gunma, Japan 4:京都大学大学院 医学研究科 高次脳形態学 / Department of Morphological Brain Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan
Neocortical neurons with similar functional properties assemble into spatially coherent circuits, but it remains unclear how inhibitory interneurons are organized in the spatial domain of the cerebral neocortex. Recent in vitro studies revealed the clusters of inhibitory interneurons originated from the same progenitor cells in the developing neocortex. However, it is still not clear how long such a clustered distribution persists during postnatal development, and even if it persists to the adulthood, it remains unknown what is the functional significance of spatial clustering of GABAergic interneurons in operation of cortical circuits.
To address these questions, we applied in vivo two-photon functional Ca2+ imaging and whole-cell recording of synaptic currents to record visual responses of cortical neurons, and analyzed their spatial arrangements. GABAergic interneurons were clustered in the three-dimensional space of the adult visual cortex, and the three subtypes of interneurons, parvalbumin-, calretinin- and somatostatin-positive neurons also formed clusters with slightly overlapping each other. Excitatory neurons located within the clusters (insiders) had a lower amplitude and sharper orientation tuning of visual responses than outsiders, whereas the neurons near and far from non-clustered interneurons did not show the location-tuning/amplitude relationship. Furthermore, inhibitory synaptic currents recorded from the insiders were larger than those of the outsiders. These findings suggest that GABAergic interneurons form spatial clusters to make their inhibitory function more effective than isolated interneurons.