DEPRESSION OF LIVER MITOCHONDRIAL COMPLEX II-LINKED RESPIRATION FOLLOWING COOLING - BENEFICIAL-EFFECTS OF USING A PROSTACYCLIN ANALOG DURING HYPOTHERMIA

The role of mitochondria in the storage and preservation of organs has not fully been investigated. We investigated the hypothesis that the addition of a prostacyclin analogue to preservation solution improved ATP regeneration profiles of stored liver by protecting mitochondrial function. Oxidative phosphorylation was investigated in isolated rat l iver mitochondria following a period of cold ischaemic preservation wi th University of Wisconsin solution plus/minus the prostacyclin analog ue, iloprost (10(-8)mol/l). In state 4 respiration (+ substrates -ADP) iloprost doubled oxygen consumption rates for both complex I and II. In state 3 (+ substrates + ADP), iloprost doubled the complex II linke d respiration rate, with no significant effect on complex I. Enzyme ac tivity of complex II, measured spectrophotometrically, showed no incre ase in the presence of iloprost. These results imply that iloprost pro tects complex II function within the inner mitochondrial membrane duri ng cold ischaemia.