Investigating the association between neural activities of anterior cingulate cortex and lower urinary tract function using optogenetics.

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K18135
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56030:Urology-related
• Research Institution: University of Yamanashi
• Principal Investigator: Shimura Hiroshi 山梨大学, 大学院総合研究部, 助教 (70755842)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: 大脳 / カルシウムイメージング / 2光子顕微鏡 / 排尿 / 前帯状皮質 / 一次運動野

Outline of Final Research Achievements

In the present study, we expressed genetically-encoded calcium indicator in anterior cingulate cortex (ACC) or primary motor cortex (M1) of mice, and two-photon calcium imaging was performed during bladder perfusion under urethane anesthesia. Micturition-related neural activity was identified in both ACC and M1 with the advantage of two-photon calcium imaging for resolving spatial distribution.
We found that the activity of individual micturition-related neurons in ACC showed a considerable variability in their timing to micturition. In particular, the timing of the activity of layer 5 pyramidal neurons in ACC showed bimodal distribution, and it depended on the projection target. On the other hand, the pattern of neural activity in M1 was rather uniform.
These results suggest that micturition-related neurons may control different aspects of voiding, e. g., initiation, maintenance and termination, depending on their location, cell-type, and projection pathway.

Free Research Field

泌尿器科

Academic Significance and Societal Importance of the Research Achievements

これまで排尿に関わる中枢神経の働きはほとんど未解明であった。特に大脳は1つの脳領域でも様々な役割を持つ神経細胞が共存している。今回の研究では2光子顕微鏡を用いることにより、個々の細胞単位で排尿に関連した活動かを判別することができた。また、同じ領域内の排尿に関連する細胞であっても、細胞によって活動のパターンが異なる場合があり、それはその細胞の存在する場所や細胞の性質、細胞の投射する経路に依存していることが明らかとなった。今回の我々のような手法を用いれば、不明瞭であった排尿に関わる中枢神経の働きを明らかにし、難治性の下部尿路機能障害の治療に大きく貢献していくと考える。