Effect of sex on TIFI in control and diabetic rats treated with and without GH. (A) STZ treatment significantly increases the TIFI in both sexes, and while GH treatment increased the TIFI in both sexes, the increase is greater in males than in females. *
P < 0.01 vs. control of the respective sex, #
P < 0.05 vs STZ of the respective sex, $
P < 0.05 vs female GH. (B) Representative pictures of Masson’s trichrome-stained sections. Diabetic kidneys were characterized by moderate tubule interstitial fibrosis, evidenced by the presence of extracellular matrix deposits (blue staining) and tubular dilation, and these changes (blue staining and larger tubules) are seen more abundantly in STZ + GH-treated animals, and most abundantly in STZ + GH-treated males. Original magnification is × 400, and bar represents 100 μm.