Inhalation and Incubation with Procaterol Increases Diaphragm Muscle Contractility in Mice

• Main Authors: Chiyohiko Shindoh, Katsuyuki Sasaki, Yuriko Shindoh, Gen Tamura
• Format: Article
• Language: English
• Published: Elsevier 2007-01-01
• Series: Allergology International
• Subjects: COPD; diaphragm muscle; endotoxin; respiratory muscle fatigue; β2-agonists
• Online Access: http://www.sciencedirect.com/science/article/pii/S1323893015308777

Background: Although procaterol is used clinically as a β2-adrenergic receptor agonist to relax airway smooth muscle, it has not yet been clarified whether procaterol has inotropic effects on respiratory muscles. Methods: Three intervention groups were investigated: a procaterol inhalation only group; a procaterol inhalation plus endotoxin injection group (in vivo); and a procaterol incubation group (in vitro). The diaphragm muscle in all groups was dissected and measurements of its contractile properties were performed. Results: The effects of procaterol inhalation shifted the force-frequency curves upward at 30 minutes after inhalation, and inhibited the decline of force-frequency curves due to endotoxin injection in vivo. In vitro administration of procaterol resulted in an increase in the force-frequency curves in a dose-dependent manner. Conclusions: It can be concluded that procaterol has an inotropic effect on the diaphragmatic muscles taken from normal animals as well as on the diaphragm muscles in a septic animal model.