Airway epithelium is a predominant source of endogenous airway GABA and contributes to relaxation of airway smooth muscle tone.

ABSTRACT: Chronic obstructive pulmonary disease and asthma are characterized by hyperreactive airway responses that predispose patients to episodes of acute airway constriction. Recent studies suggest a complex paradigm of GABAergic signaling in airways that involves GABA-mediated relaxation of airway smooth muscle. However, the cellular source of airway GABA and mechanisms regulating its release remain unknown. We questioned whether epithelium is a major source of GABA in the airway and whether the absence of epithelium-derived GABA contributes to greater airway smooth muscle force. Messenger RNA encoding glutamic acid decarboxylase (GAD) 65/67 was quantitatively measured in human airway epithelium and smooth muscle. HPLC quantified GABA levels in guinea pig tracheal ring segments under basal or st

SUBMITTER: Gallos G 

PROVIDER: S-EPMC3567364 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature