ALTERATION OF MITOCHONDRIAL LIPID-COMPOSITION IN THE PRESENCE OF DINITROPHENOL UNDER HYPOXIC CONDITIONS

Incubation of [rat] mitochondria under hypoxic conditions in hypotonic solution of sucrose containing dinitrophenol as an uncoupler of oxidative phosphorylation led to hydrolysis of mitochondrial phospholipids, with the most pronounced destruction of phosphatidyl ethanolamine and cardiolipin fractions. Hydrolysis of diacyl phospholipids was accompanied by an increase in content of the corresponding lyso-derivatives, lysophosphatidyl ethanolamine and lysocardiolipin. This phenomenon was not observed after addition of tetracaine hydrochloride, inhibitor of phospholipases, suggesting that mitochondrial phospholipases are activated under hypoxic conditions in presence of dinitrophenol.