Identification of brain regions and neural circuits involved in defecation control by the central nervous system and analysis of their functions

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K16120
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 48020:Physiology-related
• Research Institution: Kagoshima University
• Principal Investigator: NAITOU Kiyotada 鹿児島大学, 農水産獣医学域獣医学系, 准教授 (30794903)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 脊髄 / 排便 / 脳

Outline of Final Research Achievements

In this study, we used retrograde tracers to identify brain regions involved in defecation control. Adeno-associated viral vectors expressing fluorescent proteins in infected neurons were injected into the lumbosacral spinal cord, where the spinal defecation center is located, and the neurons projecting to the spinal defecation center were labeled with fluorescent proteins. Tissue sections were prepared and brain regions with fluorescent protein-labeled nerves were searched. The characteristics of the fluorescent protein-labeled nerves were further investigated by immunofluorescence staining. We also searched for neurotransmitters that act in the spinal cord and examined their mechanisms of action. These results were presented in scientific papers in English and at domestic conferences.

Free Research Field

獣医生理学

Academic Significance and Societal Importance of the Research Achievements

本研究結果から、排便制御に関わる脳領域の一部が示唆された。また、脊髄排便中枢で作用する神経伝達物質が複数明らかになった。これまで知られていなかった、脊髄排便中枢で作用する神経伝達物質が明らかになったことで、脊髄排便中枢における排便制御メカニズムの一端が明らかになった。このことは、中枢神経系による排便制御の仕組みを解明するために必要な基礎的な情報を提供し、この分野の研究の進展に貢献するものだと考えている。また、本研究の成果は、ストレス性の腹痛や下痢など、中枢神経系が深く関わる排便障害の病態を解明するために必要となる、基礎的な情報を提供しており、社会的な意義も大きい。