EVIDENCE FOR FREE-RADICAL FORMATION DURING HUMAN KIDNEY-TRANSPLANTATION

Fourteen patients undergoing kidney transplantation were studied for e vidence of the production of free radicals as assessed by the measurem ent of vitamin E (an index of lipid peroxidation) and of myeloperoxida se (a marker of neutrophil activation) in the systemic blood. Early (2 min) and late revascularization (30 min) of the kidney were respectiv ely associated with a significant decrease of 35.5 and 40% of the init ial level of plasma vitamin E. This consumption paralleled to the decr ease of the vitamin E/total lipids ratio, a better indicator of vitami n E status. Heparin administration preceding renal artery clamping res ulted in a twofold significant increase of baseline plasma myeloperoxi dase (MPO) level (523 +/- 214 ng/ml). At kidney reperfusion. MPO conce ntration rose again and reached a maximum value of 1,653 +/- 882 ng/ml , indicating the presence of considerable neutrophil activation. A ret urn to the baseline value was observed after 30 min of reperfusion. A short discussion about the possible origin of this MPO increase is giv en. Taken together, these data strongly suggest that free radical prod uction, leading to lipid peroxidation phenomena, can occur within the early phase of kidney revascularization. Preliminary data using electr on spin resonance with the spin-trapping technique strengthen this hyp othesis.