Figure 5. Ultrastructure of mitochondria of renal tubular cells in the intact kidney of young (A, B) and old (E, F) rats and those after DR (C, D and G, H, correspondingly). Renal tubular cells in young rats contain mitochondria in the orthodox configuration, while mitochondria in the old kidney demonstrate slight swelling of intercristae space and matrix. Tubular epithelium of kidney after DR exposure demonstrates noticeable condensation of the mitochondrial matrix in both young (C, D) and old (G, H) rats. Scale bar, 1 μm. For young AL rats n=5, for young DR rats n=6, for old AL rats n=6, for old DR rats n=5. AL, ad libitum, DR, dietary restriction.