Journal of Applied Physiology, Vol 51, Issue 5 1057-1064, Copyright © 1981 by American Physiological Society
Coordination of mucociliary transport in human trachea and intrapulmonary airways
D. B. Yeates, B. R. Pitt, D. M. Spektor, G. A. Karron and R. E. Albert
A wide range of both mucus velocities in the trachea and rates of bronchial
mucociliary clearance have been measured in humans. To investigate the
coordination of mucociliary transport in the intrapulmonary and
extrapulmonary airways, simultaneous measurements of tracheal mucus
velocity and lung clearance were made in 22 healthy nonsmoking adults. Each
subject inhaled several breaths of an iron oxide aerosol tagged with 99mTc.
Measurements of retained activity in the right lung were made for 2.25 h
with a pair of 5 x 2 in. NaI (T1) detectors. Tracheal mucociliary transport
rates (TMTR) were measured with a probe containing six vertically aligned
rectangular NaI (T1) detectors. The mean TMTR was 5.1 +/- 2.9 mm/min. The
mean time for the first bolus to be detected on the multidetector probe
(large airway transit time, LATT) was 52 +/- 24 min. At this time the
percent cleared (Bi) was 24 +/- 15% and the rate of clearance (Bi) was 0.64
+/- 0.35%/min. The mean percent cleared within a 2-h interval (B120) was 51
+/- 22%. The TMTR was closely correlated with Bi and Bi with B120. The TMTR
was also correlated to B120, but not closely correlated with LATT. It is
suggesting that coordination of mucus transport throughout the airways of
the lung represents the nonchallenged state and is responsible for the
maintenance of normal bronchial toilet.
