Mucociliary clearance is an important defense mechanism for clearing the lungs of bacteria and particulate matter. In a variety of airway diseases (e.g., COPD, asthma and cystic fibrosis), this becomes dysfunctional, leading to airway inflammation, obstruction and epithelial damage. Smoking has also been shown to cause a reduction in mucociliary clearance rate in humans.
At Charles River, mucociliary clearance (MCC) is measured using fluorescent beads administered to the trachea of guinea pigs. The MCC rate is increased by compounds such as beta-2 adrenergic agonists. Exposure to tobacco smoke for 4 days impairs and reduces the MCC rate, which can be reversed with beta-2 adrenergic agonists.