Understanding mechanisms for synchronous and asynchronous release of neurotransmitters at central synapses

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K06472
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 46010:Neuroscience-general-related
• Research Institution: Doshisha University
• Principal Investigator: Miki Takafumi 同志社大学, 研究開発推進機構, 准教授 (10598577)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: シナプス / シナプス小胞 / 神経伝達物質放出

Outline of Final Research Achievements

Synchronous and asynchronous release of neurotransmitters at synapses play important roles in information processing in the central nervous systems. However the mechanism for synchronous and asynchronous release remains elusive. In this study, we constructed a release model to explain temporal patterns of vesicular events upon action potentials, based on quantitative analysis of the number of released vesicles detected by the deconvolution method. From the results of the model simulation, we proposed that synaptic vesicles transit through recycling pool, replacement site and docking site before exocytosis, and that synchronous release derives from the vesicles located at docking and replacement site before an action potential arriving at presynaptic terminals, while asynchronous release derives from the vesicles located in recycling pool.

Free Research Field

分子神経生理学

Academic Significance and Societal Importance of the Research Achievements

本研究では、脳神経伝達を担う伝達物質放出の同期・非同期性放出パターンを説明する統一的な数理モデルを提唱した。同期性放出は、速く正確な神経伝達に必須である。一方、非同期性放出は持続的な神経伝達を担う。このような異なる特徴と生理的意義を持つ神経伝達を統一したモデルで理解できたことは、これまで様々な説により理解されてきた中枢シナプスの多様なシナプス特性を一般化して理解することにつながり学術的に意義深い。またこの同期・非同期性放出パターン異常は神経疾患との関連も示唆されており、今後シナプス機能改善といった疾患治療に向けた応用研究への足掛かりになる可能性がある。