Morphological analysis of reinnervation of the rat entorhino-hippocampal projections associating with spontaneous recovery of memory impairment.

• Project/Area Number: 15K09363
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Neurology
• Research Institution: Tokyo Women's Medical University
• Principal Investigator: Honda Yoshiko 東京女子医科大学, 医学部, 准教授 (40287313)
• Co-Investigator(Renkei-kenkyūsha): SHIBATA Hideshi 東京農工大学, 大学院農学研究院 動物生命化学部門 獣医解剖学研究室, 教授 (50145190) ; TOKUNO Hironobu 公益財団法人東京都医学総合研究所, 研究員 (40212071)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2017: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2016: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2015: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: 記憶 / 嗅内野 / 海馬体 / 神経線維連絡 / 海馬 / 歯状回 / 再神経支配 / 線維連絡 / 前海馬台 / 軸索投射様式

Outline of Final Research Achievements

It is known that unilateral lesion of the rat entorhinal cortex (EC) results in the significantly increased innervation (reinnervation) of the dentate gyrus from contralateral EC, suggesting spontaneous recovery of memory impairment. We aim to clarify the morphological features of axon collaterals derived from single EC neurons in such phenomenon, by comparing to the normal pattern of axonal collateralization, and also to reveal the normal entorhino-hippocampal connectional patterns in the rabbit and primate in order to establish the reinnervation models of those animal species. We confirmed that several single presubicular neurons formed complex terminal arborization in EC and the terminal distribution resembled that of the band-like terminal field seen with massive-scale observation. We also revealed that major entorhino-hippocampal connections were common in the rat, rabbit and marmoset, and that several species-specific projections were found in the rabbit and marmoset.

Research Products

• [Journal Article] Organizational connectivity among the CA1, subiculum, presubiculum, and entorhinal cortex in the rabbit (2017)
  • Author(s): Honda Yoshiko、Shibata Hideshi
  • Journal Title: The Journal of Comparative Neurology Volume: 525 Issue: 17 Pages: 3705-3741
  • DOI: 10.1002/cne.24297
  • Peer Reviewed
• [Presentation] ラット、ウサギ、マーモセットの海馬体―前海馬台―嗅内野間線維連絡 (2018)
  • Author(s): 本多祥子、柴田秀史、守屋敬子、徳野博信
  • Organizer: 第123回日本解剖学会総会・全国学術集会
• [Presentation] ウサギ海馬体、前海馬台、嗅内野を繋ぐ線維連絡 (2017)
  • Author(s): 本多祥子、柴田秀史
  • Organizer: 第122回日本解剖学会総会・全国学術集会
  • Place of Presentation: 長崎大学坂本キャンパス（長崎県長崎市）
  • Year and Date: 2017-03-27
• [Presentation] Band-like Zonal Distribution of the Cells of Origins of CA1, Subicular and Presubicular Projections in the Rabbit Entorhinal Cortex. (2016)
  • Author(s): Yoshiko Honda, Hideshi Shibata
  • Organizer: The 39th Annual Meeting of the Japan Neuroscience Society
  • Place of Presentation: パシフィコ横浜（神奈川県横浜市）
  • Year and Date: 2016-07-20
• [Presentation] Patterns of axonal collateralization of single neurons in the rat parahippocampal cortices (2015)
  • Author(s): 本多祥子
  • Organizer: The 38th Annual Meeting of the Japan Neuroscience Society
  • Place of Presentation: Kobe Convention Center（兵庫県神戸市）
  • Year and Date: 2015-07-28
  • Invited