Mucociliary function in the mouse measured in explanted lung tissue. Kurosawa, H., C. G. Wang, R. J. Dandurand, M. King, D. H. Eidelman. Meakins-Christie Laboratories, McGill University Clinic, Royal Victoria, Montreal General Hospitals, Inspiraplex Canada, Montreal, Quebec and the University of Alberta, Edmonton, Alberta, Canada
APStracts 2:0079A, 1995.
To develop a method for the study of mucociliary clearance in small caliber airways, we investigated ciliary function in an in vitro lung tissue culture technique in mice. Lungs were excised from 45 anesthetized mice (wt; 30.9g +/- 6.2 SD) and inflated with 2% liquid agarose at 37oC via the trachea. After cooling to 4oC the lungs were cut into 0.5-1.0 mm thick slices and cultured overnight. Ciliary beat frequency (CBF) was measured in airways cut in cross-section using a computerized image processing system. In some experiments charcoal particle transport (PT) in tangentially cut airways was also measured. Airway diameter ranged from 0.3 to 0.8 mm. In this preparation CBF was stable over a 3 hour period and unaffected by minor pH changes. Both CBF and PT exhibited a linear dependency on temperature. CBF and PT were significantly correlated with each other. CBF at 37oC (18.7 +/- 2.93 Hz) was almost 2-fold higher than CBF at 22oC (9.74 +/- 3.11 Hz). Isoproterenol increased CBF in a dose-dependent fashion (EC50 10-6.75M); the effect of isoproterenol could be blocked by propranolol. Administration of forskolin (10[mu]M) also increased both CBF and PT significantly. These findings demonstrate the feasibility of measuring the major aspects of mucociliary clearance in this system. This approach holds promise as a technique suitable to the investigation of both the small airways of humans and other large animals, as well as of airways in murine genetic models of respiratory disease.

Received 19 January 1994; accepted in final form 17 February
1995.
APS Manuscript Number A0054-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 10 March 1995.