ENDOGENOUS PROSTAGLANDINS REGULATE RAT RENAL PHOSPHOLIPID DE-NOVO SYNTHESIS

Rat renal papilla is the zone of the kidney enjoying the most active p hospholipid metabolism and also the highest prostanlandin production. We studied the phospholipid biosynthesis and the relationship between phospholipid de novo synthesis and prostaglandin biosynthesis in rat r enal papilla. Indomethacin inhibited the biosynthesis of phosphatidylc holine, phosphatidylinositol, phosphatidylethanolamine and phosphatidi c acid. Exogenous PGF(2 alpha) and PGD(2) restored biosynthetic activi ty in the presence of indomethacin and also increased the activity of the enzymes involved in the Kennedy pathway. The decrease in phospholi pid biosynthesis maintained a linear relationship with the decrease in prostaglandin biosynthesis. Moreover, esculetin, which stimulates pro staglandin synthesis, brought about a significant increase in P-32 inc orporation to the three phospholipids studied. The evidence presented in this paper indicates that renal PGF(1 alpha) and PGD(2) modulate ph ospholipid de novo synthesis in rat renal papilla. (C) 1997 Elsevier S cience B.V.