RESUMO
Objective: To investigate the development of tubulointerstitial fibrosis caused by partial unilateral ureter obstruction(PUUO) and the improvement of tubulointerstitial fibrosis after obstruction was relieved. Methods: PUUO was induced by the method of embedding upper half of the ureter into ipsilateral psoas.Obstruction was relieved by dissecting the ureter from psoas groove and returning its normal anatomical position.Pathology examination were performed,and collagenⅠand Ⅲ were semi-quantified by immunohistochemistry assay. Results: Massive accumulation of TypeⅠand Ⅲ collagen in tubulointerstitium leads to renal fibrosis.Renal fibrosis can recover if obstruction be relieved within 4 weeks. Conclusion: The results indicated tubuloinsterstitisl fibrosis develop progressively after PUUO,and fibrosis reduce by obstruction relief.