Histological features were evaluated using hematoxylin and eosin (H&E) staining (magnification, ×200), while immunohistochemical staining (magnification, ×400) was used to investigate the expression of nuclear factor-κB (NF-κB). Representative kidney sections stained with H&E at the end of the 24-h reperfusion period are shown for the (A) sham, (B) I/R and (C) IPoC groups. The expression of NF-κB in the kidneys at the end of the 24-h reperfusion period is shown for the (D) sham, (E) I/R and (F) IPoC groups. Sham, sham-operated; I/R, ischemia and reperfusion; IPoC, ischemic postconditioning.