In intact airways, Ach and cytoskeleton, but not dynamic Ptm determine airway diameters.

<p>Effects of static or dynamic mechanical loading conditions are shown during acetylcholine-induced (ACh) constriction in intact bovine airways in the absence (<b>A</b>) or presence (<b>B</b>) of cytoskeletal de-depolymerizing agents. Top panels show representative ultrasound images. Bottom graphs show the mean and SD of airway radii relative to pre-treatment condition (<b>A</b>; n: 9 and 10 and <b>B</b>; n: 6 and 8) CD: cytochalasin D, an actin depolymerizing agen; Noc: nocodazole, a microtubule depolymerizing agent.