Role of the hypothalamus in dyspnea perception: a basic study to develop the methods for relieving dyspnea

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K19474
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 59010:Rehabilitation science-related
• Research Institution: Aomori University of Health and Welfare (2022-2023); Uekusa Gakuen University (2020-2021)
• Principal Investigator: Fukushi Isato 青森県立保健大学, 健康科学部, 講師 (20738497)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 視床下部 / 呼吸困難感 / 呼吸リズム / オレキシン

Outline of Final Research Achievements

Mitigating dyspnea in patients with respiratory diseases is crucial in clinical settings. However, the mechanisms underlying dyspnea perception remain largely unexplored. We hypothesized the existence of a respiratory feedback control system wherein dyspnea is perceived through the transmission of ascending copy information regarding respiratory motor output from the lower brainstem to the higher brain via the hypothalamus. Furthermore, we proposed that perceived dyspnea enhances the neural drives of hypothalamic neurons to the lower brainstem. Our study demonstrated the presence of ascending neural signals corresponding to the respiratory motor output copy information from the brainstem respiratory center, identified as the motor command corollary discharge. We also identified an area in the hypothalamus exhibiting respiration-synchronized rhythmic activity and established its anatomical connection with the respiratory center in the medulla. These findings support our hypothesis.

Free Research Field

リハビリテーション科学

Academic Significance and Societal Importance of the Research Achievements

呼吸困難感とは，呼吸を行うことが容易ではないという感覚，あるいは呼吸に伴う不快感・苦痛をいう．慢性閉塞性肺疾患，肺線維症などの呼吸器疾患に罹患した患者は，労作時に体内酸素レベルが低下し，呼吸困難感を知覚することが少なくない．呼吸困難感は患者の活動量を低下させ，ひいてはQOL低下を引き起こす要因となるため，患者の呼吸困難感を軽減させることは，呼吸リハビリテーション実施上，極めて重要である．しかし，現時点で呼吸困難感の知覚機序は十分には解明されておらず，その緩和法も確立されていない．本研究成果は，呼吸困難感の知覚機序解明に寄与し，呼吸困難感の緩和法開発に寄与するものと期待される．