Investigation of inhalation effects and mechanisms on diaphragm muscle contractility

2015 Fiscal Year Final Research Report

• Project/Area Number: 25461144
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Respiratory organ internal medicine
• Research Institution: Tohoku University
• Principal Investigator: Shindoh Chiyohiko 東北大学, 医学(系)研究科(研究院), 教授 (10216228)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 吸入ステロイド剤（ICS) / 長時間作動性交感神経刺激剤（LABA） / 一酸化窒素（NO） / 気管支喘息 / 慢性閉塞性肺疾患（COPD） / 横隔膜筋

Outline of Final Research Achievements

We investigated inhalation effects on diaphragm muscle contractility using a combination of inhaled corticosteroid (ICS) and long-acting β2- agonist (LABA), and a long-acting muscarinic antagonist (LAMA). The ICS/LABA inhalation significantly increased force-frequency (F/f) curves at 1 h after inhalation. Endotoxin injection resulted in a downward shift in F/f curves at 4 h and induced NO production, however ICS/LABA inhalation prevented endotoxin effects. These results indicate that the inhalation of ICS/LABA potentiates diaphragm muscle contractility, and it seems a benefit for the patients with bronchial asthma.We also investigated inhalation effects of long-acting muscarinic antagonist (LAMA). LAMA inhalation induced an increase of muscle contractility at 4 h after its inhalation and inhibited the effects of endotoxin by reducing NO production. These results indicate that LAMA is beneficial for the patients with COPD because it helps prevent diaphragm muscle weakness.

Free Research Field

呼吸器内科学、呼吸生理学