Fig. 7.

Renal interstitial renin is induced by renal fibrosis and related to the increase in systemic blood pressure. (a) Ren1 mRNA levels in injured (I) and contralateral (C) kidneys of mice subjected to UUO for 3, 14, and 21 days. The average expression level (red bar) in non-treated kidneys (N) was set as 1. (b) Scatter plots of the relationship between systemic blood pressures (DBP, green; MBP, red; SBP, blue) and Ren1 mRNA levels in injured kidneys. R² values for the relation are shown. (c) Representative images of serial sections stained with Ren1 ISH (upper, brown) and αSMA IHC (lower, red) demonstrate that interstitial cells positive for Ren1 mRNA expression (white arrowheads) are αSMA-positive myofibroblasts in injured kidneys 21 days after UUO surgery. Ren1⁺ JG cells (red arrows) next to glomeruli (dotted circles) and renal arterioles (A) are also positive for αSMA. The scale bar represents 100 μm. (d) Quantification of Ren1 ISH in injured kidney sections from mice after UUO surgery. n = 3–4 per group. Green and brown lines indicate P<0.01 and P<0.05, respectively, in the Tukey-Kramer HSD test (a and d).