Role of intracellular glycerol-3-phosphate in the synthesis of phosphatidylglycerol by freshly isolated adult rat alveolar type II cells.
Synthesis of phosphatidylglycerol and phosphatidylinositol, phospholipid components of pulmonary surfactant, use the same precursor, CDP-diacylglycerol. In alveolar type II epithelial cells, extracellular myoinositol has been used to suppress phosphatidylglycerol synthesis, presumably by competing with glycerol-3-P for a common pool of CDP-diacylglycerol. We sought to see if extracellular lactate would increase acetate incorporation into phosphatidylglycerol by increasing glycerol-3-P. Lactate and 10 mM cytidine increased acetate incorporation into phosphatidylglycerol, whereas myoinositol and pyruvate decreased acetate incorporation into phosphatidylglycerol. Lactate increased the intracellular content of glycerol-3-P. We conclude that phosphatidylglycerol synthesis can, in part, be regulated by intracellular glycerol-3-P concentration, and we speculate that extracellular (alveolar) lactate may increase glycerol-3-P concentration in alveolar type II cells in vivo.
Mason
R J
RJ
Department of Medicine, National Jewish Center for Immunology & Respiratory Medicine, Denver, Colorado.
Voelker
D R
DR
D000818:Animals; D002794:Choline / Q000494:pharmacology; D003562:Cytidine / Q000494:pharmacology; D003596:Cytosine / Q000494:pharmacology; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D005990:Glycerol / Q000494:pharmacology; D005994:Glycerophosphates / Q000032:analysis / Q000502:physiology*; D007294:Inositol / Q000494:pharmacology; D007773:Lactates / Q000494:pharmacology; D019344:Lactic Acid; D008297:Male; D010715:Phosphatidylglycerols / Q000096:biosynthesis*; D010716:Phosphatidylinositols / Q000096:biosynthesis*; D011650:Pulmonary Alveoli / Q000166:cytology* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D005994:Glycerophosphates; D007773:Lactates; D010715:Phosphatidylglycerols; D010716:Phosphatidylinositols; D019344:Lactic Acid; D007294:Inositol; D003562:Cytidine; D003596:Cytosine; C029620:alpha-glycerophosphoric acid; D002794:Choline; D005990:Glycerol