COMPARATIVE EFFECTS OF UNIVERSITY-OF-WISCONSIN AND EURO-COLLINS SOLUTIONS ON PULMONARY MITOCHONDRIAL-FUNCTION AFTER ISCHEMIA AND REPERFUSION

Background. The aim of this study was to compare the effects of Euro-C ollins and University of Wisconsin solutions on pulmonary mitochondria l function after cold ischemia and subsequent warm reperfusion, Method s. Seventeen pigs underwent lung harvesting after classical lung flush with either University of Wisconsin or Euro-Collins solutions, The mi tochondria were isolated from fresh swine lungs, from swine lungs subj ected to 24 hr of cold ischemia, and from swine lungs subjected to 24 hr of ischemia followed by 30 min of subsequent ex vivo reperfusion at 37 degrees C with Krebs-Henseleit buffer solution and air ventilation . Mitochondrial oxidative phosphorylation parameters were determined i n isolated mitochondria by in vitro measurement of oxygen consumption rates. During reperfusion, the lung function was assessed by the pulmo nary aerodynamic parameters and the pulmonary vascular resistance.Resu lts. Relative to controls, mitochondria submitted to cold ischemia sho wed an alteration in the oxidoreductase activities of the respiratory chain, However, the yield of oxidative phosphorylation was conserved. After reperfusion, pulmonary mitochondria underwent a significant wors ening in the oxidoreductase activities of the respiratory chain, and a decrease in the respiratory control and the efficiency of oxidative p hosphorylation. Meanwhile, the reperfused lungs showed evidence of ear ly dysfunction, assessed by the aerodynamic parameters and pulmonary v ascular resistance, In this model, there was no advantage of Universit y of Wisconsin solution over Euro-Collins solution, Conclusions. The m ild mitochondrial alterations after cold ischemia were not sufficient to explain the limited tolerance of lung to ischemia. After reperfusio n, the mitochondrial damage was more severe and could be involved in t he posttransplant lung dysfunction.