[Effect of betamethasone on the lipid composition of pulmonary surfactant, ependymal cells and lung tissue after surgical procedures on the thorax of dogs].

The lipid composition of pulmonary surfactant, ependymal cells and pulmonary tissue after surgery on the thorax in dogs was determined. 24 hrs after removal of one lung, in the other one there occurred changes in the quantity of respective classes of phospholipids of the pulmonary surfactant, manifesting themselves by a considerable drop in the amount of phosphatidylcholine (by 25%), phosphatidylethylamine (by 47%), phosphatidylglycerol (by 98%) and phosphatidylcholine: sphingomyelin ratio (by 63%), as well as by a rise in the amount of lysophosphatidylcholine (by 83%), phosphatidylserine (by 54%) and sphingomyelin (by 25%). In dogs receiving betamethasone in the post-operative period the changes were less intense: the amount of phosphatidylcholine decreased by 15%, phosphatidylethanolamine by 29%, phosphatidylglycerol by 94% and phosphatidylcholine: sphingomyelin ratio by 63%. The amount of lysophosphatidylcholine increased by 26.7%, phosphatidylserine by 29.1% and sphingomyelin by 22.2%. Similar changes were observed in the phospholipids of lining cells, while changes in the composition of phospholipids of pulmonary tissue in most cases appeared insignificant. Insignificant, too, were changes in the composition of neutral lipids of the tissular fractions examined. The described changes in dogs not receiving betamethasone correspond to those found in man in the course of acute respiratory insufficiency syndrome. Betamethasone was found to exert a protective effect on the phospholipids of pulmonary surfactant, soothing the biochemical changes brought about by surgical removal of one lung.