Elucidation of synaptic input modification mechanism to neurosecretory neurons by optogenetic approach

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K06883
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 48020:Physiology-related
• Research Institution: University of Occupational and Environmental Health, Japan
• Principal Investigator: ISHII MASAHIRO 産業医科大学, 医学部, 助教 (30461560)
• Co-Investigator(Kenkyū-buntansha): 上田 陽一 産業医科大学, 医学部, 教授 (10232745)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 光遺伝学 / バゾプレッシン / シナプス入力修飾 / 神経内分泌 / パッチクランプ法

Outline of Final Research Achievements

5-7weeks old AVP-ChR2-eGFP transgenic rats　were given 2% (w/v) salt solution for 5 days. Dissociation of SON neurons from transgenic rats and electrophysiological experiments (whole-cell patch-clamp recordings from isolated SON neurons) were performed.
SON neurons isolated from salt loaded transgenic rats were used for whole-cell patch clamp recordings. In voltage clamp condition, blue light induced sustained inward currents during light-on and inward currents reduced during light-off. These suggested that ChR2 in slice function normally as cell isolation. It was clarified that the inward currents during light-on changed as the fixed membrane potential and the membrane potentials and the inward currents were in a proportional relationship.

Free Research Field

電気生理

Academic Significance and Societal Importance of the Research Achievements

スライスの状態でも細胞単離と同様にAVPニューロン中のChR2が正常に機能していることが示された。これはこの実験系でスライスと細胞単離が同一の結果を示せるかどうかという電気生理学的研究での懸念事項を解消した。また固定膜電位が変化することにより青色光照射中のinward currentも変化すること、固定膜電位とinward currentは比例関係にあることが確認でき、我々が作成したラットはヒトの生理的な興奮状態に近い現象をを再現できるとことが広く知られた。