Journal of Applied Physiology, Vol 38, Issue 5 780-785, Copyright © 1975 by American Physiological Society
Effect of vibration on isolated dog bronchi
A. S. Sinclair and M. R. Roach
Vibratory stress, induced by turbulent flow, has been shown to alter the
structural properties in arteries. Since turbulent flow can exist in the
lungs it seems important to know whether a similar effect can occur in
bronchi. To answer that question air was passed through isolated dog
bronchi. Turbulent flow was created by having, at one end, a cannula acting
as a stenosis, producing vibrations or a "flitter" in the wall. A measure
of the elastic properties was obtained by coupling pressure-volume data
with photographs taken at different pressures. The results demonstrate a
significant alteration in the structural properties, localized to ares
under maximum vibration. A "yielding" in the direction of maximum stress
was observed with a corresponding structural rearrangement (radius
decreased, length increased). This effect and its relation to structural
fatigue is discussed. The physiological significance of the results are
that the bronchi become more resistant to deformation under positive
pressures and less resistant to collapse under negative pressures.
