Renal pathological appearance and podocyte phenotype after the ureteral obstruction.

Objective To find time point of the irreversible kidney injury by observing renal pathological appearance and podocytes phenotype after complete ureteral obstruction. Methods The animal model of complete unilateral ureteral obstruction was constructed in 2-weekold and 2-month-old rats respectively. HE staining was employed to evaluate the degree of pathological changes,and immunofluorescence double staining to observe the transitional progression of podocyte. Results Grossly,there appeared pyelectasis at 2 h after obstruction and thinner renal cortex after 3 days of obstruction. Histologically,proximal tube display dilated and hydropic degeneration of tubular epithelial cells was observed after 12-day obstruction. The tubular epithelium showed distorted swelling after 3-day obstruction. Immunofluorescence double staining showed that podocytes decreased and the double-labeled macrophages was increased during 1 d to 2 d after unilateral ureteral obstruction operation. Conclusion Compared with control groups,the unilateral ureteral obstruction groups shows podocyte-to-macrophage transition at 1 d after the operation,while the pelvis shows obviously dilated. From the 1st day to the 7th day after unilateral ureteral obstruction,it shows increasing tendency of the podocytes transition.