Metabolism of phospholipids in rat kidney during development.

We have examined the phospholipid content and metabolism in renal papilla, medulla and cortex in 10- to 70-day-old rats. No changes in papillary and medullary phospholipids with an increase in cortical phosphatidylcholine and phosphatidylethanolamine were evident during maturation. Phosphatidylinositol de novo synthesis did not change with age, but a decrease in medullary and cortical phosphatidylcholine and phosphatidylethanolamine was observed. In the three zones [14C]arachidonic acid incorporation into all the phospholipids was the highest at 10 days with a gradual decrease with age, while the [14C]palmitic acid incorporation remained unchanged except for phosphatidylinositol which decreased from 10 to 70 days.