Urinary endothelin (ET1) in complete ureteric obstruction in the miniature pig

Segmental renal scarring occurs in experimental obstructive uropathy in the multipapillary porcine kidney, and segmental abnormalities in renal perfusion are likely to be responsible. This preliminary study examines the urinary excretion of the potent locally active vasoconstrictor endothelin 1 (ET 1) in a pig model of renal obstruction and subsequent relief. Significant urinary excretion of ET 1 from the postobstructive kidney was found to occur after longstanding obstruction. Preglomerular arteriolar stenosis may be the cause of the renal ischaemia in obstruction that is at first reversible but later becomes irreversible if the stimulus persists. ET 1 may be implicated in the pathogenesis of this injury.