Figure 1.

Thermotropic behavior of native pulmonary surfactant and membranes reconstituted from its fractions. DSC thermograms were obtained from suspensions of native pulmonary surfactant purified from porcine lungs (NPS), or reconstituted from surfactant organic extract containing all the lipids and the hydrophobic proteins (NPSE), the whole lipid fraction of surfactant depleted of proteins (NPSL), or the phospholipid fraction of surfactant (NPSP) resulting from removal of proteins and neutral lipids from the organic extract. Suspensions with 1 mg/mL phospholipid concentration were scanned at 0.5 K/min. The dashed line marks 37°C.