PXSL » Topics » How do the lungs clear mucus?

This excerpt taken from the PXSL 6-K filed Oct 10, 2006.

How do the lungs clear mucus?

The inside lining of our airways is covered by millions of fine hair-like structures called cilia, which are in turn covered by a thin layer of mucus, secreted by the lungs to defend against germs, dust particles and other foreign bodies.

In lung cells, salt moves through ion channels in the cell membrane to the airway surface. The chloride and sodium combination pulls water into the lungs to create a thin fluid layer that coats the airway surface and keeps the cilia moist so they can do their job of moving foreign particles along the airway and out of the lungs. The cilia move continuously and propel the overlying blanket of salt, water and mucus up to the throat, where secretions are swallowed or expelled as sputum (this process is called mucociliary clearance).

This constant process, which is barely noticeable in healthy people, helps keep the airways clean, allows the passage of clean, warm air through the lungs, and removes any foreign bodies from the airways, preventing infection.

People with respiratory diseases such as Chronic Obstructive Pulmonary Disease (COPD) and cystic fibrosis are generally affected by a breakdown in the natural mechanism of cleansing, hydrating, and protecting the mucus lining their airways. They face the ongoing challenge of clearing excessive and thickened secretions from their congested lungs, usually by constant coughing.

This excerpt taken from the PXSL 6-K filed Nov 3, 2005.

How do the lungs clear mucus?

The inside lining of our airways is covered by millions of fine hair-like structures called cilia, which are in turn covered by a thin layer of mucus, secreted by the lungs to defend against germs, dust particles and other foreign bodies.

In lung cells, salt moves through chloride channels in the cell membrane to the airway surface. Then, just as a dry sponge soaks up water, the chloride and sodium combination pulls water into the lungs to create a thin fluid layer that coats the airway surface and keeps the cilia moist so they can do their job of moving foreign particles along the airway and out of the lungs. The cilia move continuously and propel the overlying blanket of salt, water and mucus up to the throat, where secretions are swallowed or expelled as sputum (this process is called mucociliary clearance).

This constant process, which is barely noticeable in healthy people, helps keep the airways clean, allows the passage of clean, warm air through the lungs, and removes any foreign bodies from the airways, preventing infection.

People with COPD (and with cystic fibrosis) are generally affected by a breakdown in the natural mechanism of cleansing, hydrating, and protecting the mucus lining their airways. They face the ongoing challenge of clearing excessive and thickened secretions from their congested lungs, usually by constant coughing.

EXCERPTS ON THIS PAGE:

6-K
Oct 10, 2006
6-K
Nov 3, 2005