UUO: This model is induced in mice or rats by unilateral ureteral ligation (UUO) of the left ureter. The animals rapidly develop, within a few days, severe tubulo-interstitial renal fibrosis with an inflammatory cell infiltrate in the affected kidney. rnrnSNX: This model consists at reducing the renal mass by 83%. This induces hyperfiltration and induces over a period of around 6 months significant fibrotic lesions in C57bl/6j mice and in 2 months in Swiss mice. In rats the model is somewhat faster as it induces renal fibrosis in 3 months.