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Superoxide and hydroxyl free radicals are strongly implicated in the deleterious effects of reperfusion of grafted organs. Iron ions are critical in the Fenton-like reaction that generates oxygen-free radicals from H2O2. Using the ADP/Fe2+/H2O2 .OH-generating system, we demonstrated that components of an organ-preservation solution (Henri Mondor solution): sodium lactobionate, adenine, and a nitroxide radical: 4-hydroxy-2,2,6,6-tetramethylpiperidine-n-oxyl (TEMPOL), showed unexpected inhibition properties on the production of hydroxyl radicals by complexation of Fe2+ for lactobionate and nitroxide or Fe3+ for adenine. This inhibition was 75.5% at 12 mM lactobionate. Moreover, a complete inhibition was observed at 50 mM. At 0.25 mM adenine, the reduction was 14.8% (maximum effect: 34.1%). Henri Mondor solution, at an identical adenine and lactobionate concentration, inhibited the radical production by 91.5%, indicating an additive effect. Nitroxide totally inhibited .OH production by the ADP/Fe2+/H2O2 system (maximum effect: 95.6%) and partially the production by an O2.- generating system (maximum effect: 74.8%). Thus, the association of these three components in preservation solutions would be an original method to limit the reperfusion injury observed in isolated ischemic organs.