Figure 4 A photomicrograph of renal tissue sections. (a) Normal structure of glomeruli and tubules. (b) Rats treated with toluene show vacuolar degeneration of tubular epithelial lining (arrow) with dilatation of some tubules and urinary space in some glomeruli (arrowhead). (c) Rats treated with toluene and 150 mg citicoline, where dilatation and degeneration of epithelial lining of tubules are still noticed. (d) Rats treated with toluene and 300 mg citicoline show no vacuolar degenerated epithelial lining cells, although signs of edema and dilatation of tubules are observed (hematoxylin and eosin, ×200).