Journal of Applied Physiology, Vol 58, Issue 6 1823-1831, Copyright © 1985 by American Physiological Society

ARTICLES

Reflex tracheal contraction evoked in dogs by bronchodilator prostaglandins E2 and I2

A. M. Roberts, H. D. Schultz, J. F. Green, D. J. Armstrong, M. P. Kaufman, H. M. Coleridge and J. C. Coleridge

Bronchodilator prostaglandins E2 and I2 may cause airway irritation and bronchoconstriction in human subjects. These experiments were designed to test the hypothesis that this paradoxical bronchoconstriction is a vagal reflex triggered by stimulation of airway afferents. We recorded smooth muscle tension in an innervated upper tracheal segment in anesthetized dogs and injected prostaglandins into the general circulation or into a bronchial artery or administered them as aerosol to the lungs. Prostaglandins usually caused tracheal contraction, which survived vagal cooling to 5-7 degrees C but was abolished at 0 degrees C. Vagally mediated tracheal contraction was also evoked when prostacyclin was injected into the pulmonary circulation of dogs whose pulmonary and systemic circulations were independently pump perfused. Recordings of afferent vagal impulses indicated that bronchial arterial injection of prostaglandins stimulated bronchial C-fibers; aerosols of prostaglandin stimulated pulmonary and bronchial C-fibers and C-fibers in extrapulmonary airways. We postulate that in susceptible human subjects concentrations of these prostaglandins too low to have direct bronchodilator effects may cause reflex bronchoconstriction by stimulating afferent vagal C-fibers in the lower airways.

This article has been cited by other articles:

				L.-Y. Wang, F. J. Cerny, T. J. Kufel, and B. J. B. Grant Simulated obesity-related changes in lung volume increases airway responsiveness in lean, nonasthmatic subjects. Chest, September 1, 2006; 130(3): 834 - 840. [Abstract] [Full Text] [PDF]

				B. J. Canning Reflex regulation of airway smooth muscle tone J Appl Physiol, September 1, 2006; 101(3): 971 - 985. [Abstract] [Full Text] [PDF]

				E. F. Bailey and R. F. Fregosi Modulation of upper airway muscle activities by bronchopulmonary afferents J Appl Physiol, August 1, 2006; 101(2): 609 - 617. [Abstract] [Full Text] [PDF]

				D. R. Bergren Prostaglandin involvement in lung C-fiber activation by substance P in guinea pigs J Appl Physiol, June 1, 2006; 100(6): 1918 - 1927. [Abstract] [Full Text] [PDF]

				K. F. Chung Evaluation of Selective Prostaglandin E2 (PGE2) Receptor Agonists as Therapeutic Agents for the Treatment of Asthma Sci. Signal., September 27, 2005; 2005(303): pe47 - pe47. [Abstract] [Full Text] [PDF]

				Z.'i. Wajima, T. Shiga, T. Yoshikawa, A. Ogura, K. Imanaga, T. Inoue, and R. Ogawa Intravenous Alprostadil, an Analog of Prostaglandin E1, Prevents Thiamylal-Fentanyl-Induced Bronchoconstriction in Humans Anesth. Analg., August 1, 2003; 97(2): 456 - 460. [Abstract] [Full Text] [PDF]

				S. L. Tilley, J. M. Hartney, C. J. Erikson, C. Jania, M. Nguyen, J. Stock, J. McNeisch, C. Valancius, R. A. Panettieri Jr., R. B. Penn, et al. Receptors and pathways mediating the effects of prostaglandin E2 on airway tone Am J Physiol Lung Cell Mol Physiol, April 1, 2003; 284(4): L599 - L606. [Abstract] [Full Text] [PDF]

				M. J. Marantz, S. G. Vincent, and J. T. Fisher Role of vagal C-fiber afferents in the bronchomotor response to lactic acid in the newborn dog J Appl Physiol, June 1, 2001; 90(6): 2311 - 2318. [Abstract] [Full Text] [PDF]

				J. R. Sheller, D. Mitchell, B. Meyrick, J. Oates, and R. Breyer EP2 receptor mediates bronchodilation by PGE2 in mice J Appl Physiol, June 1, 2000; 88(6): 2214 - 2218. [Abstract] [Full Text] [PDF]

				V. Diaz, D. Dorion, I. Kianicka, P. Letourneau, and J.-P. Praud Vagal afferents and active upper airway closure during pulmonary edema in lambs J Appl Physiol, May 1, 1999; 86(5): 1561 - 1569. [Abstract] [Full Text] [PDF]