How does surfactant work in the lungs?
How does surfactant work in the lungs?
Surfactant is released from the lung cells and spreads across the tissue that surrounds alveoli. This substance lowers surface tension, which keeps the alveoli from collapsing after exhalation and makes breathing easy.
What is surfactant in physiology?
Surfactant: A fluid secreted by the cells of the alveoli (the tiny air sacs in the lungs) that serves to reduce the surface tension of pulmonary fluids; surfactant contributes to the elastic properties of pulmonary tissue, preventing the alveoli from collapsing.
Where is surfactant in the lungs?
alveolar surface
Pulmonary surfactant is a complex and highly surface active material composed of lipids and proteins which is found in the fluid lining the alveolar surface of the lungs.
Where is surfactant found in lungs?
How is surfactant formed?
Surfactant is synthesized and secreted by Type II alveolar epithelial cells, also called pneumocytes, which differentiate between 24 and 34 weeks of gestation in the human. It is made up of 70% to 80% phospholipids, approximately 10% protein and 10% neutral lipids, mainly cholesterol [3].
What is the main active ingredient in lung surfactants?
dipalmitoylphosphatidylcholine
The main phospholipid in surfactant is dipalmitoylphosphatidylcholine (DPPC), also known as lecithin. It is surface active because of its hydrophilic head and hydrophobic tails (Figure 46-7).
What is the surfactant in the lungs?
Surfactant is an agent that decreases the surface tension between two media. The surface tension between gaseous-aqueous interphase in the lungs is decreased by the presence of a thin layer of fluid known as pulmonary surfactant. The pulmonary surfactant is produced by the alveolar type-II (AT-II) cells of the lungs.
What is surfactant and its importance?
The main function of surfactant is to lower the surface tension at the air/liquid interface within the alveoli of the lung. This is needed to lower the work of breathing and to prevent alveolar collapse at end-expiration.