TEMPERATURE-DEPENDENT PHOSPHOLIPID DEGRADATION IN THE RAT-LIVER DURING PRESERVATION FOR TRANSPLANTATION - A COMPARISON BETWEEN DIFFERENT PRESERVATION SOLUTIONS

For the development of liver injury during preservation for transplant ation, phospholipid degradation may be of importance. We therefore mea sured the degradation of [H-3]-arachidonic acid (20:4)- and [C-14]-lin oleic acid (18:2)-labeled phospholipids during cold and warm preservat ion of rat livers in Eurocollins, University of Wisconsin, or a recent ly developed dextrans-based solution. The amount of labeled phospholip ids decreased with time during preservation at 37 degrees C with a con comitant increase in that of labeled fatty acids. The rate of degradat ion of [H-3]-20:4-labeled phospholipids did not differ from that of [C -14]-18:2-labeled phospholipids. The reduction of phosphatidylcholine and phosphatidylethanolamine radioactivity accounted for the major red uction of phospholipid radioactivity while there was no decrease in ph osphatidylinositol radioactivity. In contrast, no phospholipid hydroly sis occurred during: preservation at 4 degrees C or at 21 degrees C. T he results were not different whether the livers were preserved in EC, UW, or the dextran-based preservation solution. During reperfusion of livers either immediately after removal or after cold storage at 4 de grees C in EC or UW solutions for 24 hr, a moderate increase in the [H -3] and [C-14] radioactivity of free fatty acids and triacylglycerol a nd in that of [H-3] in PE occurred. There was, however, no difference between the three groups. Thus, during liver preservation at 37 degree s C, phospholipid degradation occurs, and its rate is independent of t he preservation medium. In contrast, at the temperature used when pres erving livers for transplantation, there is no phospholipid degradatio n. The cold storage in either EC or UW solution does not influence the net hydrolysis and the transesterification reaction that the phosphol ipids undergo during warm reperfusion of the isolated livers.