Airway diameter determines flow-resistance and sensitivity to contractile mediators in perfused bronchial segments.
To study airway reactivity, flow-resistance to carbachol and histamine was measured in perfused bronchial segments. Small-bore airways were more sensitive, flow was reduced to zero and resistance rose very steeply due to mucosal folding while in large-bore airways maximum flow reduction was 50% and resistance increased sigmoidly. Thus the internal diameter of an airway is a crucial determinant of narrowing.
Sparrow
M P
MP
Department of Physiology, University of Western Australia, Nedlands.
Willet
K E
KE
Mitchell
H W
HW
D000403:Airway Resistance; D000818:Animals; D001980:Bronchi / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D016085:Bronchoconstrictor Agents / Q000494:pharmacology*; D004558:Electric Stimulation; D066298:In Vitro Techniques; D009424:Nervous System Physiological Phenomena; D010477:Perfusion; D012123:Pulmonary Ventilation; D013552:Swine
D016085:Bronchoconstrictor Agents