Journal of Applied Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 63: 221-228, 1987;
8750-7587/87 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by van Lunteren, E.
Right arrow Articles by Cherniack, N. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by van Lunteren, E.
Right arrow Articles by Cherniack, N. S.

Journal of Applied Physiology, Vol 63, Issue 1 221-228, Copyright © 1987 by American Physiological Society

ARTICLES

Respiratory changes in thoracic muscle length during bronchoconstriction

E. van Lunteren, M. A. Haxhiu, E. C. Deal Jr, J. S. Arnold and N. S. Cherniack

The purpose of the present study was to assess the effects of bronchoconstriction on respiratory changes in length of the costal diaphragm and the parasternal intercostal muscles. Ten dogs were anesthetized with pentobarbital sodium and tracheostomized. Respiratory changes in muscle length were measured using sonomicrometry, and electromyograms were recorded with bipolar fine-wire electrodes. Administration of histamine aerosols increased pulmonary resistance from 6.4 to 14.5 cmH2O X l-1 X s, caused reductions in inspiratory and expiratory times, and decreased tidal volume. The peak and rate of rise of respiratory muscle electromyogram (EMG) activity increased significantly after histamine administration. Despite these increases, bronchoconstriction reduced diaphragm inspiratory shortening in 9 of 10 dogs and reduced intercostal muscle inspiratory shortening in 7 of 10 animals. The decreases in respiratory muscle tidal shortening were less than the reductions in tidal volume. The mean velocity of diaphragm and intercostal muscle inspiratory shortening increased after histamine administration but to a smaller extent than the rate of rise of EMG activity. This resulted in significant reductions in the ratio of respiratory muscle velocity of shortening to the rate of rise of EMG activity after bronchoconstriction for both the costal diaphragm and the parasternal intercostal muscles. Bronchoconstriction changed muscle end-expiratory length in most animals, but for the group of animals this was statistically significant only for the diaphragm. These results suggest that impairments of diaphragm and parasternal intercostal inspiratory shortening occur after bronchoconstriction; the mechanisms involved include an increased load, a shortening of inspiratory time, and for the diaphragm possibly a reduction in resting length.


This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
A. B. Sprikkelman, L. A. Van Eykern, M. S. Lourens, H. S. A. Heymans, and W. M. C. Van Aalderen
Respiratory muscle activity in the assessment of bronchial responsiveness in asthmatic children
J Appl Physiol, March 1, 1998; 84(3): 897 - 901.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online