Respiratory control in kidney and liver mitochondria isolated from rats treated with the potent nephrotogenic amino-nucleoside of puromycin

Rates of oxygen uptake of kidney mitochondria from normal and aminonucleoside-nephrotic rats have been determined by means of an oxygen electrode. The rates of oxygen uptake in state 3 (as defined by Chance and Williams) were lower for nephrotic rat kidney mitochondria than for normal kidney mitochondria. This change suggests that kidney mitochondrial enzymes from aminonucleoside-nephrotic rats may be decreased in amount, activity, or accessibility. It is also possible that mitochondria from aminonucleoside-nephrotic rats are less capable of maintaining structural integrity, and thus are damaged more during the isolation procedure. When livers of nephrotic rats were used as the source of mitochondria, impairment of respiratory control was not observed but, in fact, respiratory control ratios were higher than those of normal rat liver mitochondria. Respiratory rates were also obtained by preincubating normal kidney and liver mitochondria with aminonucleoside. No pronounced effect of aminonucleoside upon normal rat kidney mitochondria was observed in vitro.