The temporal relationship between the severity of hydroureter and the dynamic changes of obstructed ureters in a rat model

摘要: Objective To investigate dynamic changes in the obstructed rat ureter and to evaluate the usefulness of the rat model in the study of obstructive uropathy. Materials and methods Unilateral ligation of the ureter was performed in 26 rats. After ureteric ligation, four to seven rats were killed and examined after 1, 3, 7, 10, and 14 days. The severity of hydroureter and hydronephrosis was assessed by pyelography and the hydroureter‐hydronephrosis index. The middle portion of the ureter was prepared for light and electron microscopic observation. Five rats which received a sham operation were also examined as controls. Results The severity of hydroureter and hydronephrosis in the ligated ureters progressively increased during the period of obstruction (P < 0.005) and reached a maximum 10–14 days after ligation. Hypertrophy of the smooth muscle layer developed on the third day after ligation and proliferation of …