title: Rheological properties of microliter quantities of normal mucus.
abstract: Microliter quantities of normal canine tracheobronchial mucus were obtained by direct sampling from the tracheas of anesthetized dogs. The rheological properties of the mucus samples were determined using a newly developed magnetic rheometer. The data show a very rapid decrease in dynamic viscosity with increasing frequency, and a much less rapid increase in elasticity. Mean values of elasticity and viscosity at 1 rad-s-1 for seven dogs were ca. 300 dyn-cm-2 and ca. 75 P, respectively. The steady-state viscosity values were ca. 3 X 10(4) P, i.e., two orders of magnitude higher than the highest dynamic values measured. The significance of the rheological behavior in terms of the clearance of secretions from the lung is discussed.
mesh_terms: D000818:Animals; D001980:Bronchi; D004285:Dogs; D004548:Elasticity; D008433:Mathematics; D008954:Models, Biological; D009093:Mucus; D012212:Rheology; D014132:Trachea; D014783:Viscosity