Long-term renal effects of unilateral ureteral obstruction and the role of endothelin

Kidney Int. 2000 Jul;58(1):242-50. doi: 10.1046/j.1523-1755.2000.00159.x.

Abstract

Background: Angiotensin II (Ang II) and endothelin (ET) are involved in the alteration of renal function in unilateral ureteral obstruction (UUO). The renal response to Ang II following the reversal of a 24-hour UUO and the effect of ET blockade by bosentan during the time of obstruction were investigated.

Methods: Following blockade of the endogenous production of Ang II by captopril, the renal response to Ang II was studied in rats 15 to 18 days after a 24-hour UUO (N = 10) or a sham operation (N = 9) both with (N = 10) and without (N = 8) bosentan treatment in the periobstruction period. Similar studies were performed in another group (N = 9) two months following the reversal of obstruction.

Results: In the sham-operated group, Ang II reduced renal blood flow (RBF) by 42 +/- 9% (P < 0.01), glomerular filtration rate (GFR) by 30 +/- 8% (P < 0.01), urine volume (UV) by 44 +/- 9% (P < 0.001), and absolute (UNaV) and fractional sodium excretion (FENa) by 52 +/- 9% (P < 0.001) and 33 +/- 9% (P = 0.054), respectively. In the previously obstructed kidney, Ang II did not change RBF but increased GFR by 106 +/- 40% (P < 0.01), UV by 75 +/- 21% (P < 0.001), UNaV by 190 +/- 60% (P < 0.001), and FENa by 40 +/- 13% (P < 0.05). Bosentan treatment in the obstructed group prevented these Ang II-induced effects and did not have any effect on the sham-operated kidney. Two months following reversal of the obstruction, the response of the kidney was similar to that of the control kidney.

Conclusion: Twenty-four-hour UUO results in a temporary abnormality in the renal response to Ang II, which is due, in part, to the actions of ET at the time of obstruction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin II / pharmacology
  • Angiotensin-Converting Enzyme Inhibitors / pharmacology
  • Animals
  • Antihypertensive Agents / pharmacology
  • Blood Pressure / drug effects
  • Bosentan
  • Captopril / pharmacology
  • Endothelins / metabolism*
  • Hypertension, Renal / drug therapy
  • Hypertension, Renal / metabolism*
  • Male
  • Rats
  • Rats, Wistar
  • Sulfonamides / pharmacology
  • Ureteral Obstruction / drug therapy
  • Ureteral Obstruction / metabolism*
  • Urodynamics / drug effects
  • Vasoconstrictor Agents / pharmacology

Substances

  • Angiotensin-Converting Enzyme Inhibitors
  • Antihypertensive Agents
  • Endothelins
  • Sulfonamides
  • Vasoconstrictor Agents
  • Angiotensin II
  • Captopril
  • Bosentan