Showing papers by "Richard J. King published in 1985"

Lipid Synthesis and Surfactant Turnover in the Lungs

Abstract: The sections in this article are: 1 Lipid Composition of Lung Tissue 1.1 Parenchyma 1.2 Alveolar Type II Cells 1.3 Pulmonary Surfactant 2 Metabolic Pathways of Lipids in Lung Tissue 2.1 Phosphatidylcholine 2.2 Phosphatidylglycerol 2.3 Other Lipids in Surfactant 2.4 Enzymes of Lipid Synthesis 3 Regulation of Surfactant Metabolism 3.1 Regulation of Synthesis and Storage of Surfactant Components 3.2 Regulation of Secretion of Surfactant Components 3.3 Regulation of Clearance of Surfactant Components 3.4 Relationship Between Protein and Lipid Metabolism 4 Compartmental Analysis in Studies of Surfactant Turnover

Composition and Metabolism of the Apolipoproteins of Pulmonary Surfactant

Abstract: It seems difficult to believe, in light of to day's sophisticated morphology, that as recently as 40 years ago pulmonary biologists still thought it possible that gas exchange might occur across capillaries that were directly exposed to the alveolar air (30). With the development of a more realistic viewpoint of alveolar morphology, encompassing an alveolar epithelium with an overlying fluid layer, much older questions (47) concerning the stability of air spaces received renewed interest. Macklin (33), Pattie (37), Clements (9), and Mead (36) and their collaborators asked how it was possible that alveoli were able to resist the collapsing forces that would result from the surface tension of the alveolar air-liquid interface. Pattle and Clements provided partial answers to these questions through their isolation and characterization of a material se­ creted by alveolar epithelial type II cells, which they then showed to be capable of lowering surface tension to values less than had ever been observed for a biological substance, This material is now generally referred to as pulmonary surfactant. When isolated from alveolar lavage fluid it has been found to be comprised of several lipids, specific apolipoproteins, and carbohydrates (20). The structure is complex and poorly understood (48). This paper will review information related to the composition and metabo­ lism of this material, focusing on the newer results that are pertinent. Studies on the physicochemical properties and physiological functions of surfactant