Surfactants identified in lung lymph and their ability to act as abhesives.
Phospholipid has been extracted from pulmonary lymph collected from 10 dogs. Thin-layer chromatography was used to identify phosphatidylcholine (PC) 55.6 +/- 2.9%, sphingomyelin 21.3 +/- 1.7%, phosphatidylethanolamine 11.2 +/- 4.9%, and lysophosphatidylcholine 5.9 +/- 0.8%. All extracts proved highly surface active, reducing the surface tension of saline to 27.7 +/- 0.7 dyn/cm upon 80% film compression and increasing the maximum contact angle on glass (theta) from 7 +/- 1 to 47.4 +/- 1.4 degrees. The hydrophobic properties induced on glass were further demonstrated by the ability to cause saline to withdraw and expose a dry surface. A standard adhesion test was used to measure the "tack" produced by the major proteins in lymph. However, when the surface energy of the hydrophilic glass surfaces was reduced by a monolayer of lymph phospholipid extract or an equivalent mixture of synthetic surfactants, the adhesive force was reduced by 79 +/- 4% for albumin and 55 +/- 4% for globulin. As a 0.1% liposomal suspension, PC gave 55% release with albumin. Reversible bonding of the lumen of lymph vessels by the "tacky" proteins present is discussed as a possible factor contributing to the large changes in flow resistance known to occur in the pulmonary lymphatic system.
D000269:Adhesives / Q000494:pharmacology; D000818:Animals; D002855:Chromatography, Thin Layer; D004285:Dogs; D008168:Lung / Q000032:analysis* / Q000502:physiology; D008196:Lymph / Q000032:analysis*; D008208:Lymphatic System / Q000502:physiology; D010743:Phospholipids / Q000032:analysis* / Q000494:pharmacology; D011663:Pulmonary Surfactants / Q000032:analysis* / Q000494:pharmacology; D013501:Surface-Active Agents / Q000494:pharmacology
D000269:Adhesives; D010743:Phospholipids; D011663:Pulmonary Surfactants; D013501:Surface-Active Agents