Hydrophobic lung surfactant proteins B and C remain associated with surface film during dynamic cyclic area changes.
The biophysical activity of lung surfactant depends, to a large extent, on the presence of the hydrophobic surfactant proteins B (SP-B) and C (SP-C). The role of these proteins in lipid adsorption and lipid squeeze-out under dynamic conditions simulating breathing is not yet clear. Therefore, the aim of this study was to investigate the interaction of spread hydrophobic surfactant proteins with phospholipids in a captive-bubble surfactometer during rapid cyclic area changes (6 cycles/min). We found that SP-B and SP-C facilitated the rapid transport of lipids into the air-water interface in a concentration-dependent manner (threshold concentration > or = 0.05:0.5 mol% SP-B/SP-C). Successive rapid cyclic area changes did not affect the concentration-dependent lipid adsorption process, suggesting that SP-B and SP-C remained associated with the surface film.
Putz
G
G
Department of Anesthesia and Intensive Care Medicine, Leopold-Franzens-University of Innsbruck, Austria. guenther.putz@uibk.ac.at
Walch
M
M
Van Eijk
M
M
Haagsman
H P
HP
D010743:Phospholipids / Q000737:chemistry*; D011510:Proteolipids / Q000737:chemistry*; D011663:Pulmonary Surfactants / Q000737:chemistry*; D013500:Surface Tension