Partial ureteric obstruction: a new variable canine experimental model.

An experimental model of ureteric obstruction should be accurate and persistent, and allow variation of the degree of obstruction. A model was tested in 28 dogs consisting of insertion of an obstructing stent into the left ureter, and the degree of obstruction was varied by altering the internal diameter of the stents. The effects of such an obstruction on the following features were studied: renal intrapelvic pressure, intravenous urography, creatinine clearance, vascular casts, and both gross and histological examination. The procedure was well tolerated and caused a persistent, unchanging degree of partial ureteric obstruction. Pathological changes of obstructive uropathy were produced. This model can be used for further pathophysiological studies.