Altered prostaglandin synthesis by glomeruli from rats with unilateral ureteral ligation

There is evidence that prostaglandins modulate renal hemodynamics in unilateral ureteral obstruction. We examined prostaglandin synthesis by glomeruli from rats with 24- and 72-h unilateral ureteral ligation. During prelabeling of the lipid pools with [¹⁴C]arachidonate glomeruli from the ligated kidney incorporated less ¹⁴C label than those from contralateral or normal control kidneys. However, the incorporation of [¹⁴C]arachidonate into phospholipids of glomeruli was proportionately higher in the ligated kidney. Incubation of the prelabeled glomeruli with either angiotensin II or bradykinin significantly increased release of labeled prostaglandins and turnover of [¹⁴C]arachidonate on the ligated side. Radioimmunoassay determinations showed that after 24-h ligation, glomeruli from both sides produced comparable amounts of PGF(2α) 6-keto-PGF(1α) TXB₂, and PGE₂. After 72 h, glomeruli from the ligated kidney produced more PGF(2α), 6-keto-PGF(1α) and TXB₂ than the contralateral glomeruli. In contrast PGE₂ synthesis was higher in contralateral glomeruli. Neither angiotensin II nor bradykinin had a measurable effect on radioimmunoassayable prostaglandins. We conclude that unilateral ureteral ligation is associated with specific alterations of glomerular prostaglandin synthesis and phospholipid metabolism that are intrinsic to the glomerulus.