Figure 5.

Elimination of UUO stress restores the normal Epo-producing potential. (A) Representative photographs of the UUO reversal model using vascular clips (Clip-ClipR treatment). We obstruct the left ureter by a vascular clip for 2 days (Clip). The vascular clip is removed 2 days after the obstruction, and then mice are euthanized 12 days after the removal (ClipR-14). (B) Recovery of Epo-producing potential of G-REPs in UUO-treated kidneys after the clip removal. Real-time PCR analysis is performed to quantify Epo-GFP mRNA levels, which are expressed as the relative expression compared with the contralateral (Cont) kidney. **P<0.01 versus sham and ClipR-14 (n=5 per group). (C) Changes of fibrogenic markers during Clip-ClipR treatment. Real-time PCR analyses are performed to quantify Acta2, Col1a1, and Col3a1 mRNA expressions using kidneys of sham, Clip, and ClipR-14 groups. ***P<0.01 versus sham and contralateral kidneys (n=5 per group). (D) Schematic presentation for the cell-fate analyses of REPs upon Clip-ClipR treatment. (E) Distribution of ON-REPs (Epo-GFP⁺ cells) and total REPs (tdTomato⁺ cells) upon Clip-ClipR treatment. Immunohistochemical analysis performed for Epo-GFP and tdTomato using kidneys of ISAM::Epo-Cre::R26T. (F and G) Changes in cell number of ON-REPs and total REPs upon Clip-ClipR treatment. FACS analyses are performed to count the number of Epo-GFP⁺ cells and tdTomato⁺ cells in ClipR-14 kidneys and contralateral (Cont) kidneys (n=5). Cont, contralateral; IHC, immunohistochemical analysis; NS, not significant. Scale bar in E, 200 μm.