Ultrastructural alteration in the rat liver produced by benzyl viologen.

This report presents qualitative data of the effects of a free radical generator (benzyl viologen) on rat liver. Rats were administered benzyl viologen (0.825 mg per kg of body weight) or saline solution (controls) intraperitoneally, in single daily dosage for 15 days. For microscopic examination animals were killed after 3 or 15 days of treatment. In the control animals, liver ultrastructure remained normal throughout the experiment. But in rats with benzyl viologen it was possible to observe important morphological alterations essentially in mitochondria, frequently forming ring-like bodies. Endoplasmic reticulum was observed as concentric patterns which cover the mitochondria and, on occasion, the lipid droplets within the cell. Increased number of dense granular lysosomes were observed in the apical cytoplasm mainly close to the bile canaliculus. A large quantity of lipid inclusions and cellular degeneration of the liver of treated rats showed a marked dose-response relationship.