Immunohistochemical analysis of HMGB1 expression in the study groups. Representative images of sections immunohistochemically stained for HMGB1 in a WKY-NTS (−) rat (a, b) are shown. HMGB1 was stained in podocytes (a), parietal epithelial cells (a) and tubular epithelial cells (b) (arrows). Kidney sections were stained using two-color immunohistochemistry with ED1 stained red and HMGB1 stained brown in a WKY-Vehicle rat (c, d). Original magnifications, ×400 (b, c) and ×1000 (a, d). Scale bar, 50 μm (a, d) and 100 μm (b, c).