HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free All Versions of this Article: 101/1/249    most recent 01010.2004v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Chen, B. Articles by Solway, J. Search for Related Content PubMed PubMed Citation Articles by Chen, B. Articles by Solway, J.

Tidal breathing pattern differentially antagonizes bronchoconstriction in C57BL/6J vs. A/J mice

¹Section of Pulmonary and Critical Care Medicine, University of Chicago; ²Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas; ³Harvard School of Public Health, Boston, Massachusetts; and ⁴Northwestern University, Evanston, Illinois

Submitted 14 September 2004 ; accepted in final form 9 January 2006

There is abundant evidence that tidal breathing, and especially tidal breathing at elevated minute ventilation, antagonizes the development and persistence of airflow obstruction during bronchoconstrictor stimulation in normal animals and people. Here, we studied the antiobstructive effect of different tidal breathing patterns in C57Bl/6J and A/J mice during bronchoconstriction induced by continuous or bolus infusion of methacholine. Anesthetized, paralyzed mice were mechanically ventilated at 1,500 ml·kg^–1·min^–1, using each of three breathing patterns: 5 ml/kg, 300 breath/min; 10 ml/kg, 150 breath/min; or 20 ml/kg, 75 breath/min. Changing from 10 ml/kg, 150 breath/min to 20 ml/kg, 75 breath/min, breathing functionally antagonized bronchoconstriction, reducing the level of airflow obstruction induced by methacholine infusion or boluses equivalently in both strains. In marked contrast, changing from 10 ml/kg, 150 breath/min to 5 ml/kg, 300 breath/min, breathing substantially exacerbated methacholine-induced airflow obstruction in A/J mice, whereas it had no significant effect in C57Bl/6J mice. Our results therefore demonstrate that 1) even at moderate, fixed minute ventilation, the precise breathing pattern can influence the degree of airflow obstruction substantially, and 2) the influence of breathing pattern on bronchoconstriction differs considerably between genetically diverse inbred mouse strains. These findings imply that differences in antiobstructive effects of breathing can contribute to differences in apparent airway constrictor responsiveness. Much attention has been placed on dysregulation of contractile function of airway smooth muscle in human disease. We suggest that important pathophysiology might also be found in impairment of the functional antagonist effect of tidal breathing on airflow obstruction.

asthma; deep inhalation; airway; mouse

This article has been cited by other articles:

				M. J. Sanderson, P. Delmotte, Y. Bai, and J. F. Perez-Zogbhi Regulation of Airway Smooth Muscle Cell Contractility by Ca2+ Signaling and Sensitivity Proceedings of the ATS, January 1, 2008; 5(1): 23 - 31. [Abstract] [Full Text] [PDF]

				T. T. B. Nguyen and J. J. Fredberg Strange Dynamics of a Dynamic Cytoskeleton Proceedings of the ATS, January 1, 2008; 5(1): 58 - 61. [Abstract] [Full Text] [PDF]

				R. W. Mitchell, M. L. Dowell, J. Solway, and O. J. Lakser Force Fluctuation induced Relengthening of Acetylcholine-contracted Airway Smooth Muscle Proceedings of the ATS, January 1, 2008; 5(1): 68 - 72. [Abstract] [Full Text] [PDF]

				J. Solway and C. G. Irvin Airway Smooth Muscle as a Target for Asthma Therapy N. Engl. J. Med., March 29, 2007; 356(13): 1367 - 1369. [Full Text] [PDF]