Hydroperoxide-induced radical production in liver mitochondria.

When isolated rat liver mitochondria are treated with tert-butyl hydroperoxide in the presence of the spin trap 5,5-dimethyl-1-pyrroline-N-oxide, a six-line ESR signal is observed with parameters characteristic of a carbon-centered radical. The radical is shown to be CH3. using 2-methyl-2-nitrosopropane as the spin trap. Inhibition of radical production by EDTA and N-ethylmaleimide provides evidence for participation by metals and reduced sulfhydryl groups in the radical-generating reaction. It is proposed that radicals are formed through the reaction between a reducing agent, a metal and the hydroperoxide.