Histological fibrotic changes in the tubulointerstitium.

(A) Masson-trichrome (Masson) staining showing renal tubulointerstitial morphology. Bar = 100 μm. (B) Collagen IV (COLAIV) staining showing tubule interstitial fibrotic change. Bar = 100 μm. WT-vehicle, control WT mice (n = 8); WT-Ald, WT-aldosterone infusion mice (n = 8); eNOSKO-vehicle, control eNOS KO mice (n = 8); eNOSKO-Ald, eNOS KO-aldosterone infusion mice (n = 8). (C) Tubulointerstitial injury score (0–4), (D) tubulointerstitial fibrosis area (%), and (E) COLA IV positive area (%). Data are shown as mean ± SEM. *P †P ‡P <0.05 vs. eNOSKO-vehicle.