Exploration of the non-systematic organizing principle of the brain that coexists with and share the same tissue space with the systematic organizing priciple

2018 Fiscal Year Final Research Report

• Project/Area Number: 16KT0174
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 特設分野
• Research Field: Constructive Systems Biology
• Research Institution: Kumamoto University
• Principal Investigator: Fukuda Takaichi 熊本大学, 大学院生命科学研究部(医), 教授 (50253414)
• Research Collaborator: Shigematsu Naoki
• Project Period (FY): 2016-07-19 – 2019-03-31
• Keywords: GABA / インターニューロン / ギャップ結合 / 海馬 / 歯状回

Outline of Final Research Achievements

Distribution pattern of parvalbumin (PV)-positive neurons that are major GABAergic interneurons in the hippocampus and neocortex was explored using immunohistochemical method and mathematical analysis. PV neurons in the CA1 region of the hippocampus were distributed in both the stratum pyramidale and a thin lamina at the border between the stratum oriens and alveus. Somata of the latter population showed a random pattern with their dendrites extending in the same lamina and forming gap junction-coupled plexus. PV neurons in the dentate gyrus were also distributed in a thin lamina between the granule cell layer and hilus, showed a random pattern, and formed gap junction-coupled dendritic nets in the lamina. These structures are thought to facilitate flexible regulation of neuronal activities involved in memory formation.

Free Research Field

神経解剖学

Academic Significance and Societal Importance of the Research Achievements

これまでの神経科学は、脳における情報処理過程の解明において、その緻密な秩序的構成に注目して解析が行われてきた。しかしながら、情報処理を担うニューロン群と並立する制御システムニューロン（GABA作動性インターニューロン）の解剖学的構造は、むしろ無秩序性に基づいた構成原理を示唆している。本研究は、このことをマウスの海馬において明らかにし、記憶形成回路に革新的見方をもたらした。