Simultaneous canine tracheal transport of different particles.

We describe a method to study simultaneously the transport of 2 different markers in the canine trachea. In our studies, we found that choice of radioisotopic label and variation in marker size from 3 to 180 micrometer did not affect the transport rate of basic anion exchange resin particles. Furthermore, anion exchange and acidic cation exchange particles of the same size had similar tracheal transport rates. This method may help to determine the influence of the physicochemical properties of markers on mucous transport.