Isolated rat-liver nuclei were incubated with a series of membrane-permeable metal-ion-complexing agents and examined for DNA damage. Of the reagents tested, only 1,10-phenanthroline (OP) and neocuproine (NC) were found to induce DNA fragmentation. Agarose-gel electrophoresis of the DNA fragments generated in the presence of OP revealed internucleosomal cleavage, which is widely considered to b...
