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: 102/3/859    most recent 00884.2006v1 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 ISI Web of Science 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 (4) Citing Articles via Google Scholar Google Scholar Articles by Ito, S. Articles by Suki, B. Search for Related Content PubMed PubMed Citation Articles by Ito, S. Articles by Suki, B.

Effects of heterogeneities on the partitioning of airway and tissue properties in normal mice

¹Department of Biomedical Engineering, Boston University, Boston, Massachusetts; and ²Department of Respiratory Medicine, Nagoya University School of Medicine, Nagoya, Japan

Submitted 10 August 2006 ; accepted in final form 26 November 2006

We measured the mechanical properties of the respiratory system of C57BL/6 mice using the optimal ventilation waveform method in closed- and open-chest conditions at different positive end-expiratory pressures. The tissue damping (G), tissue elastance (H), airway resistance (Raw), and hysteresivity were obtained by fitting the impedance data to three different models: a constant-phase model by Hantos et al. (Hantos Z, Daroczy B, Suki B, Nagy S, Fredberg JJ. J Appl Physiol 72: 168–178, 1992), a heterogeneous Raw model by Suki et al. (Suki B, Yuan H, Zhang Q, Lutchen KR. J Appl Physiol 82: 1349–1359, 1997), and a heterogeneous H model by Ito et al. (Ito S, Ingenito EP, Arold SP, Parameswaran H, Tgavalekos NT, Lutchen KR, Suki B. J Appl Physiol 97: 204–212, 2004). Both in the closed- and open-chest conditions, G and hysteresivity were the lowest and Raw the highest in the heterogeneous Raw model, and G and H were the largest in the heterogeneous H model. Values of G, Raw, and hysteresivity were significantly higher in the closed-chest than in the open-chest condition. However, H was not affected by the conditions. When the tidal volume of the optimal ventilation waveform was decreased from 8 to 4 ml/kg in the closed-chest condition, G and hysteresivity significantly increased, but there were smaller changes in H or Raw. In summary, values of the obtained mechanical properties varied among these models, primarily due to heterogeneity. Moreover, the mechanical parameters were significantly affected by the chest wall and tidal volume in mice. Contribution of the chest wall and heterogeneity to the mechanical properties should be carefully considered in physiological studies in which partitioning of airway and tissue properties are attempted.

chest walls; elastance; mechanical force; mechanical stretch; modeling

This article has been cited by other articles:

				K. Huang, R. Rabold, E. Abston, B. Schofield, V. Misra, E. Galdzicka, H. Lee, S. Biswal, W. Mitzner, and C. G. Tankersley Effects of leptin deficiency on postnatal lung development in mice J Appl Physiol, July 1, 2008; 105(1): 249 - 259. [Abstract] [Full Text] [PDF]

				R. H. Brown, D. W. Kaczka, K. Fallano, S. Chen, and W. Mitzner Temporal variability in the responses of individual canine airways to methacholine J Appl Physiol, May 1, 2008; 104(5): 1381 - 1386. [Abstract] [Full Text] [PDF]

				A. Thammanomai, L. E. Hueser, A. Majumdar, E. Bartolak-Suki, and B. Suki Design of a new variable-ventilation method optimized for lung recruitment in mice J Appl Physiol, May 1, 2008; 104(5): 1329 - 1340. [Abstract] [Full Text] [PDF]