Cadmium Toxicity and Liver Mitochondria I. Different Effects of Cadmium Administered In Vivo to Adult, Young, and Ethionine-Fed Rats

The changes in liver mitochondria] respiratory activities and cytochrome concentrations were investigated when cadmium chloride was administered orally to adult, young, and ethionine-fed rats. Following a seven-day administration of 30 ppm cadmium in drinking water, adult rats showed no change, while young rats and ethionine-fed rats exhibited a marked increase in mitochondrial respiration with concomitant decrease of respiratory control index and P/O ratio. The concentrations of cytochromes aa3, b, and c+cx in liver mitochondria were un-changed in adult rats, but increased significantly in ethionine-fed rats. In young rats receiving cadmium the liver mitochondrial protein increased with a slight change in the cytochrome concentration in mitochondria. It was further found that in adult rats a higher concentration (300 ppm) of cadmium in drinking water was toxic to the liver mitochondrial functions. Thus, the effect of oral administration of cadmium on the liver mitochondrial function depends on the condition of the animals. In vitro, cadmium (Cd) inhibits a number of The liver also accumulates massive amounts of enzymes having functional sulfhydryl groups, Cd (8-11). However, there have been few reports affects the amounts of cellular constituents, and on Cd-induced liver damage (cf. 12). It seem