Study On Hydronephrosis And Renal Fibrosis Caused By Partial Unilateral Ureter Obstruction

Objective: â‘  To establish a ideal animal model of partial unilateral ureter obstruction (PUUO). â‘¡ To investigate the degree of hydronephrosis,the change of renal function, and the development of tubulointerstitial fibrosis caused by PUUO. â‘¢ To study the improvement of hydronephrosis,renal function and tubulointerstitial fibrosis after obstruction is relieved. Methods: 144 male SD rats underwent left nephrectomy,and were then randomly assigned into three groups: â‘  24 rats in group 1 (Control group) underwent only left nephrectomy. â‘¡ 24 rats in group 2 (Obstruvtive group) were subjected to right upper ureter obstruction by the method of embedding upper half of the ureter into ipsilateral psoas. In group 1 and group 2, renal function were determinated,ultrasound and pathology examination were performed,and Typeâ… and â…¢collagen were semi-quantified by immunohistochemistry assay at 1, 2, 4, and 8 weeks after the operation. â‘¢ 96 rats of group 3 (Release group)were established PUUO as above mentioned, and then relieved the obstruction by dissecting the ureter from psoas groove and returning its normal anatomical position at 1, 2, 4, and 8 weeks after PUUO (R1, R2, R4, R8).the obstruction relieved rats were sacrificed at 1, 2, 4, and 8 after renal function, collagenâ… and collagenâ…¢ were measured, and ultrasound examination were performed. Results: â‘  The collecting-system of the obstructed kidney is dilated progressively, APD and V are higher,and RCT is thinner than those of control group at every intervals. hydronephrosis recovered after relief of obstruction, earlier relief means quicker improvement. â‘¡ Infiltration of fibroblasts, dilation of tubules,and the apoptosis and atrophy of tubular epithelial occurred progressively with the presence of PUUO.These changes can recover if obstruction be released within 8 weeks after PUUO. â‘¢ Serum creatine ascended, and GFR reduced 2 weeks after obstruction,massive accumulation of Typeâ… and â…¢ collagen in tubulointerstitium leads to renal fibrosis. These changes can recover progressively if obstruction can be relieved within 8 weeks. Conclusion: â‘  Embedding upper half of ureter into ipsilateral psoas produced a severe partial obstruction, and obstruction can be easily reversed by dissecting the ureter from psoas groove and returning its normal anatomical position. â‘¡ Damage of renal function and interstitial fibrosis deteriorate progressively after PUUO. â‘¢Renal function and tubuloinsterstitial fibrosis recover time-dependedly if obstruction be relieved within 8 weeks, earlier relief may gain better restoration, but renal function and tubuloinsterstitisl fibrosis will not recover if obstruction was relieved 8 weeks later.