ABSTRACT
1. Probucol treatment of mice (0.6 g/kg) induced a decrease of cholesterol (CH) and total phospholipids (PLs) in blood plasma, erythrocyte ghosts, liver plasma and microsomal membranes. 2. The incorporation of [14C]acetate in the microsomal lipids of probucol-treated mice was lowered by 23% compared to controls. 3. Probucol administration induced a reduced specific activity of PLs, CH and CH esters, whereas in triacylglycerols it was augmented. 4. Phospholipase A2 and neutral sphingomyelinase activities were not enhanced, indicating that the catabolism of the membrane PL was not elevated.
Subject(s)
Erythrocyte Membrane/chemistry , Lipid Metabolism , Liver/chemistry , Membrane Lipids/metabolism , Probucol/pharmacology , Acetates/metabolism , Acetic Acid , Animals , Cell Membrane/chemistry , Cholesterol/blood , Cholesterol/metabolism , Cholesterol Esters/blood , Lipids/blood , Membrane Lipids/blood , Mice , Microsomes, Liver/metabolism , Phospholipases A/metabolism , Phospholipases A2 , Phospholipids/blood , Phospholipids/metabolism , Sphingomyelin Phosphodiesterase/metabolism , Triglycerides/metabolismABSTRACT
We investigated the extent of the influence of maternal diabetes on the phospholipid composition and exchange activity of the neonatal lung alveolar surfactant. The results show that each phospholipid fraction (as well as the total phospholipid content) of the surfactant of neonates with diabetic mothers are decreased to about 30% of the control values. Phosphatidylcholine and phosphatidylglycerol, which are the most important surface active phospholipid fractions, were decreased to 27% and 34% respectively. In lung tissue of the neonates with diabetic mothers, all phospholipid fractions were increased. We found that the phosphatidylcholine-exchange activity in the alveolar surfactant does not exist in neonates with diabetic mothers. This inhibited phospholipid-exchange activity may be the reason for the decrease in the surfactant phospholipids and their increase in the lungs of neonates with diabetic mothers. The cholesterol content in the surfactant of such neonates decreased by almost half in comparison with the controls, while in lung tissue it remained unchanged. Producing an experimental respiratory distress syndrome could permit to study more deeply the causes which provoke it and the accompanying metabolic changes.
Subject(s)
Animals, Newborn/metabolism , Diabetes Mellitus, Experimental/metabolism , Maternal-Fetal Exchange , Phospholipids/analysis , Pregnancy Complications , Pulmonary Surfactants/analysis , Animals , Female , Humans , Infant, Newborn , Pregnancy , Rats , Rats, Inbred Strains , Respiratory Distress Syndrome, Newborn/metabolismABSTRACT
The phospholipid composition of mitochondria, microsomes and plasma membranes from liver and MC-29 hepatoma from White Leghorn chickens has been investigated. It was established that all mitochondria and microsome phospholipid fractions obtained from MC-29 hepatoma are increased strongly compared to those from liver. The sphingomyelin augmentation was particularly great. In hepatoma plasma membranes only the sphingomyelin quantity was increased. Sphingomyelin- and phosphatidylcholine-exchange activities were observed in avian liver for the first time. These two activities were increased in MC-29 hepatoma cells. Three phospholipid-exchange proteins have been established in chicken liver 105000 X g supernatant. One of them specifically transports phosphatidylcholine, the second one is non-specific for phosphatidylcholine and sphingomyelin, and the third one is specific only for sphingomyelin. In hepatoma cells only a non-specific phosphatidylcholine- and sphingomyelin-exchange protein was found.
Subject(s)
Carrier Proteins/metabolism , Chickens/metabolism , Liver/metabolism , Membrane Proteins , Phospholipid Transfer Proteins , Phospholipids/metabolism , Animals , Cell Membrane/metabolism , Liposomes , Liver Neoplasms, Experimental/metabolism , Microsomes, Liver/metabolism , Mitochondria, Liver/metabolism , Phosphatidylcholines/metabolism , Sphingomyelins/metabolism , Subcellular Fractions/metabolismABSTRACT
Investigations have been carried out for the determination of the effect of high oxygen concentration in inspired gas mixutre on the positional distribution of fatty acids in rabbit lung phospholipids and triacylglycerols. The following results were obtained: 1. In the phosphatidylcholine fraction, the high oxygen concentration caused a quantitative increase of palmitic acid (16 : 0) at the alpha-position, and of myristic (14 : 0), heptadecenic (17 : 1) and arachidonic (20 : 4) acids at the beta-position. 2. In t-e phosphatidylethanolamine fraction, the high oxygen concentration caused an increase of oleic acid (18 : 1) at the alpha-position, and of palmitoleic (16 : 1) and heptadecenic (17 : 1) acids at the beta-position. 3. In the triacylglycerol fraction such changes were not observed. In connection with these effects of oxygen, its possible influence on membrane structures in the lung has been discussed.
