SHORT-TERM AND LONG-TERM TREATMENT WITH INDOMETHACIN CAUSES RENAL PHOSPHOLIPID ALTERATION - A POSSIBLE EXPLANATION FOR INDOMETHACIN NEPHROTOXICITY

Phospholipid content was studied in kidneys from rats treated with ind ometacin. Short-term treatment was performed by using low(l and 5 mg/k g/day) and high(10 and 50 mg/kg/day) doses of indometacin. Long-term t reatment was achieved by using only low doses of indometacin. Short-te rm treatment at low doses did not result in any change in the phosphol ipid content. In rats administered higher concentrations, indometacin caused a marked increase in all papillary phospholipid contents, but n o effect was observed in the medulla, and an increase in sphingomyelin and phosphatidylethanolamine was observed in the cortex. Long-term tr eatment with administration of 1 mg/kg/day of indometacin led to an in crease in all papillary phospholipids from the 2nd week of treatment. Medullary phospholipids also increased, but no changes were observed i n cortical phospholipids. These results show that indometacin causes p hospholipid accumulation in rat kidney and that the papilla is the mos t sensitive renal tissue.