title: The in vivo labeling with acetate and palmitate of lung phospholipids from developing and adult rabbits.
abstract: The labeling with radiolabeled acetate and palmitate of lung, microsomes isolated from lung, and surfactant phospholipids from adult, 3-day-old, and newborn rabbits was studied. The half-life of phosphatidylcholine from lung and microsomal fractions was shorter when labeled with acetate than when labeled with palmitate. Half-time values similarly measured for phosphatidylglycerol, phosphatidylinositol or phosphatidylethanolamine were not different for the two labels. Acetate and palmitate-labeled phospholipids appeared in the surfactant fraction with similar accumulation curves. The relative specific activities of acetate-labeled phosphatidylcholine from adult, 3-day-old, and newborn rabbits, respectively, were 1.30, 1.86 and 1.77 times those measured for those measured for the palmitate label. Surfactant phosphatidylinositol and phosphatidylethanolamine from 3-day-old animals similarly were labeled preferentially with acetate. However, phosphatidylglycerol purified from the surfactant fraction contained equivalent relative amounts of the acetate and palmitate labels in 3-day-old and adult rabbits. These results suggest that the type II pneumocyte may use acetate preferentially for the synthesis of palmitic acid which then is incorporated into surfactant phospholipids.
mesh_terms: D000085:Acetates / Q000378:metabolism*; D000375:Aging; D000818:Animals; D005260:Female; D006207:Half-Life; D008168:Lung / Q000378:metabolism*; D008861:Microsomes / Q000378:metabolism; D010168:Palmitates / Q000378:metabolism*; D010169:Palmitic Acids / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010715:Phosphatidylglycerols / Q000378:metabolism; D010716:Phosphatidylinositols / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D011247:Pregnancy; D011663:Pulmonary Surfactants / Q000378:metabolism; D011817:Rabbits
chemical_list: D000085:Acetates; D010168:Palmitates; D010169:Palmitic Acids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010715:Phosphatidylglycerols; D010716:Phosphatidylinositols; D010743:Phospholipids; D011663:Pulmonary Surfactants