Eicosanoid production by isolated glomeruli of rats with unilateral ureteral obstruction

Eicosanoid production by isolated glomeruli of rats with unilateral ureteral obstruction. The production of PGE 2 6-keto PGF lα and TxB 2 under basal conditions and after exposure to angiotensin II was examined in vitro in isolated glomeruli from sham-operated control rats and rats with unilateral ureteral obstruction of 24 hour duration, that were or were not pretreated with an inhibitor of the angiotensin I converting enzyme (ACE). Basal prostanoid production was greater in glomeruli from the obstructed kidney (OK) than in glomeruli from the contralateral kidney (CLK) of rats with obstruction or glomeruli from the kidneys of sham-operated rats. Glomeruli obtained from the CLK of rats with unilateral obstruction also produced more PGE 2 and 6-keto PGF lα than glomeruli obtained from kidneys of sham-operated rats. Administration of an ACE inhibitor to rats with unilateral obstruction in vivo returned basal prostanoid production in vitro to levels seen in glomeruli of sham-operated rats, The increase in prostanoid production in response to angiotensin II added in vitro was less in glomeruli from rats with unilateral obstruction than in glomeruli from sham-operated rats. However, the response was restored to that seen in glomeruli of sham-operated rats after blockade of angiotensin II synthesis in vivo in rats with unilateral obstruction. Blockade of angiotensin II synthesis in sham-operated rats did not affect prostanoid synthesis by their glomeruli. The results indicate that endogenous angiotensin II has an important role in the increased synthesis of prostanoids found not only in glomeruli of the OK but also of the CLK of rats with unilateral obstruction and that the in vitro prostanoid production in response to angiotensin II can be restored to that seen in sham-operated rats when the synthesis of angiotensin II is inhibited in vivo.