抄録
The effect of di-(2-ethylhexyl) phthalate (DEHP) on oxidative phosphorylation of isolated rat liver mitochondria was investigated. DEHP at concentrations of 20-1000 μM had no effect no state 4 respiration, but at 40 μM, DEHP decreased the rate of state 3 respiration by about 20%. Although DEHP had no effect on electron transport through the respiratory chain, it decreased the rate of adenosine triphosphate (ATP) synthesis. Its inhibition of ATP synthesis showed a similar concentration dependence to that of state 3 respiration. Furthermore, DEHP at 40 μM inhibited the uptake of [3H] adenosine diphosphate into mitochondria. DEHP also retarded the action of cationic uncoupling agents, which are known to modify the 29000-dalton protein involved in adenine nucleotide exchange. These results suggest that DEHP affects the activity of adenine nucleotide exchange and consequently partially decreases the rate of state 3 respiration. The action of DEHP on the 29000-dalton protein involves a protective effect against mitochondrial damage induced by hydrophobic cations or heavy metal cations.
