Oxidative phosphorylation of rat liver and kidney mitochondria after Cd intoxication and the preventive effect of Mg

Experimental acute intoxication from cadmium chloride in the rat was studied with specific reference to change in the activity of mitochondrial oxidative phosphorylation in the liver and kidney. Various concentrations of cadmium chloride (2.5, 5.0, 10.0 mg/Kg) were given by intraperitoneal injection. Two hours after cadmium injection, the activity of liver and kidney mitochondrial oxidative phosphorylation had decreased, suggesting that cadmium uncoupled oxidative phosphorylation in liver and kidney mitochondria. A dose response relationship of cadmium uncoupling was observed in liver mitochondria, but was not observed in kidney mitochondria indicating that kidney mitochondria were more sensitive to cadmium than liver mitochondria were. A single injection of 250 mg/Kg of magnesium chloride prevented the uncoupling action of cadmium in liver mitochondria but not in kidney mitochondria. Magnesium did not prevent the uncoupling action of mercury chloride in liver or kidney mitochondria. The preventive action of magnesium chloride was evident in in vitro liver mitochondria but not in in vitro kidney mitochondria. The effect of magnesium on cadmium action was discussed.