Thromboxane A2 induces airway constriction through an M3 muscarinic acetylcholine receptor-dependent mechanism.

Published

Journal Article

Thromboxane A2 (TXA2) is a potent lipid mediator released by platelets and inflammatory cells and is capable of inducing vasoconstriction and bronchoconstriction. In the airways, it has been postulated that TXA2 causes airway constriction by direct activation of thromboxane prostanoid (TP) receptors on airway smooth muscle cells. Here we demonstrate that although TXA2 can mediate a dramatic increase in airway smooth muscle constriction and lung resistance, this response is largely dependent on vagal innervation of the airways and is highly sensitive to muscarinic acetylcholine receptor (mAChR) antagonists. Further analyses employing pharmacological and genetic strategies demonstrate that TP-dependent changes in lung resistance and airway smooth muscle tension require expression of the M2 mAChR subtype. These results raise the possibility that some of the beneficial actions of anticholinergic agents used in the treatment of asthma and chronic obstructive pulmonary disease result from limiting physiological changes mediated through the TP receptor. Furthermore, these findings demonstrate a unique pathway for TP regulation of homeostatic mechanisms in the airway and suggest a paradigm for the role of TXA2 in other organ systems.

Full Text

Duke Authors

Cited Authors

  • Allen, IC; Hartney, JM; Coffman, TM; Penn, RB; Wess, J; Koller, BH

Published Date

  • March 2006

Published In

Volume / Issue

  • 290 / 3

Start / End Page

  • L526 - L533

PubMed ID

  • 16243899

Pubmed Central ID

  • 16243899

International Standard Serial Number (ISSN)

  • 1040-0605

Digital Object Identifier (DOI)

  • 10.1152/ajplung.00340.2005

Language

  • eng

Conference Location

  • United States