Property of the Monolayers of Cow Lung Lipids

Abstract

There is a lipid monolayer on the surface of the alveolus of animal lung. It decreases the surface tension of water in the alveolus and has an important effect on the function of the lung. Lipid separated from cow lung tissue was found to contain dipalmitoyl phosphatidyl choline in a high concentration. The monolayer of the lung phosphatidyl choline exhibited a marked hysteresis, and this hysteresis was considered to be correlated with the lung mechanics. It was found that this hysteresis became larger when the monolayer was compressed to higher surface pressure, and also that it depended on temperature and was the largest at about 30°. It was concluded that the hysteresis was caused by the phase transition of the monolayer by compression. The behavior of the monolayers of phosphatidyl ethanolamine and sphingomyeline separated from cow lung tissue was also discussed.