Effect of 1,25-dihydroxyvitamin D3 on phospholipid composition of rat renal brush border membrane.
To analyze the effects of vitamin D on renal tubular cell membrane phospholipid metabolism, the effects of vitamin D depletion and repletion on renal brush border membrane (BBM) phosphatidylethanolamine (PE), phosphatidylcholine (PC), and phosphatidylinositol (PI) were studied. The PC content of BBM from kidneys of rats deprived of vitamin D for 5-6 wk was 33.5 +/- 2.2 nmol Pi/mg protein. This was significantly lower than the PC content of BBM from kidneys of rats supplemented with vitamin D2 for 2 wk, 41.0 +/- 0.4 nmol Pi/mg protein. Vitamin D depletion also decreased the content of BBM PE. The fatty acid composition of BBM PC was altered by vitamin D depletion. Vitamin D depletion increased palmitic acid and decreased stearic, linoleic, and arachidonic acid. Vitamin D repletion with a single physiological dose of 1,25(OH)2D3 (30 pmol), 16 h prior to study tended to increase membrane content of PC and significantly increased the linoleic acid content of the PC fraction. Single-dose vitamin D repletion with a pharmacological dose of 1,25(OH)2D3 (2.4 nmol) produced a significant increase in BBM content of PC and also significantly increased the linoleic acid content of PC. These results demonstrate that vitamin D deficiency affects PC and PE content of rat renal BBM and their fatty acid composition, and that vitamin D repletion with 1,25(OH)2D3 for 16 h partially normalizes the changes in PC.
D000818:Animals; D002117:Calcitriol / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D007668:Kidney / Q000378:metabolism*; D008297:Male; D008871:Microvilli / Q000187:drug effects / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010716:Phosphatidylinositols / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D014808:Vitamin D Deficiency / Q000378:metabolism
D005227:Fatty Acids; D010710:Phosphates; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010716:Phosphatidylinositols; D010743:Phospholipids; D002117:Calcitriol; D002118:Calcium