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


     

J Appl Physiol 86: 66-70, 1999;
8750-7587/99 $5.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
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
Right arrow Citation Map
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 Salerno, F. G.
Right arrow Articles by Ludwig, M. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Salerno, F. G.
Right arrow Articles by Ludwig, M. S.
Vol. 86, Issue 1, 66-70, January 1999

Elastic moduli of excised constricted rat lungs

Francesco G. Salerno and Mara S. Ludwig

Meakins-Christie Laboratories, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada H2X 2P2

When airways constrict, the surrounding parenchyma undergoes stretch and distortion. Because of the mechanical interdependence between airways and parenchyma, the material properties of the parenchyma are important factors that modulate the degree of bronchoconstriction. The purpose of this study was to investigate the effect of changes in transpulmonary pressure (Ptp) and induced constriction on parenchymal bulk (k) and shear (µ) moduli. In excised rat lungs, pressure was measured at the airway opening, and pressure-volume curves were obtained by imposing step decreases in volume with a calibrated syringe from total lung inflation. Calculation was made of k during small-volume oscillations (1 Hz). Absolute lung volume at 0 cmH2O Ptp was obtained by saline displacement. To calculate µ, a lung-indentation test was performed. The lung surface was deformed with a cylindrical punch (diameter = 0.45 cm) in 0.25-mm increments, and the force required to effect this displacement was measured by a weight balance. Measurements of k and µ were obtained at 4 and 10 cmH2O Ptp, and again at 4 cmH2O Ptp, after delivery of methacholine aerosol (100 mg/ml) into the trachea. Values of k and µ in rat lungs were similar to those reported in other species. In addition, k and µ were dependent on Ptp. After induced constriction, k and µ increased significantly. That k and µ can increase after induced constriction has important implications vis a vis the factors modulating airway narrowing.

shear modulus; bulk modulus; mechanical interdependence; bronchoconstriction


This article has been cited by other articles:


Home page
 Eur Respir JHome page
C. Y. Seow
Are you pulling my airway?
Eur. Respir. J., November 1, 2005; 26(5): 759 - 761.
[Full Text] [PDF]

Home page
 Am. J. Respir. Crit. Care Med.Home page
A. DUGUET, C.-G. WANG, R. GOMES, H. GHEZZO, D. H. EIDELMAN, and R. S. TEPPER
Greater Velocity and Magnitude of Airway Narrowing in Immature Than in Mature Rabbit Lung Explants
Am. J. Respir. Crit. Care Med., November 1, 2001; 164(9): 1728 - 1733.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Respir. Crit. Care Med.Home page
W. MITZNER and R. H. BROWN
Potential Mechanism of Hyperresponsive Airways
Am. J. Respir. Crit. Care Med., May 1, 2000; 161(5): 1619 - 1623.
[Abstract] [Full Text]

Home page
 J. Appl. Physiol.Home page
F. G. Salerno, N. Shinozuka, J. J. Fredberg, and M. S. Ludwig
Tidal volume amplitude affects the degree of induced bronchoconstriction in dogs
J Appl Physiol, November 1, 1999; 87(5): 1674 - 1677.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
R. S. Tepper, B. Wiggs, S. J. Gunst, and P. D. Pare
Comparison of the shear modulus of mature and immature rabbit lungs
J Appl Physiol, August 1, 1999; 87(2): 711 - 714.
[Abstract] [Full Text] [PDF]


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