Cholinergic trigger drives synaptic plasticity for stress avoidance task

2015 Fiscal Year Final Research Report

• Project/Area Number: 25460314
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental physiology(including physical medicine and nutritional physiology)
• Research Institution: Yamaguchi University
• Principal Investigator: MITSUSHIMA Dai 山口大学, 医学(系)研究科(研究院), 教授 (70264603)
• Co-Investigator(Renkei-kenkyūsha): KIDA Hiroyuki 山口大学, 大学院医学系研究科, 助教 (70432739) ; ISHIKAWA Junko 山口大学, 大学院医学系研究科, 助教 (30570808) ; SAKIMOTO Yuya 山口大学, 大学院医学系研究科, 助教 (40634390)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ストレス / 学習・記憶 / AMPA受容体 / GABAA受容体 / シナプス可塑性 / パッチクランプ法

Outline of Final Research Achievements

Acute stress forms strong episodic memory, being useful to avoid similar stress in future. Learning of stressful context by the inhibitory avoidance task strengthens not only AMPA receptor-mediated excitatory synapses, but also GABAA receptor-mediated inhibitory synapses, showing wide-diversity of synaptic input after the contextual learning in rats. Learning requires the diversity of synapses, since blocking to forms diversity successfully impaired the learning. CA1 neurons showed rapid synaptic diversity within 5 min after the episode, and we observed the diversity both sides of hippocampus, in right and left hemisphare. Moreover, self-entoropy analysis of the diversity revealed the amount of information at the synapses. The total self-entropy at synapses in 400000 CA1 neurons was estimated 5.6 x 1000000 bit after the learning.

Free Research Field

生理学、神経科学