Effect of prostacycline analogue OP-41483 and perfusate on liver preservation by simple hypothermia in rats.

Changes in rat livers preserved by simple cooling immersion in modified Sacks' solution, Ross' solution and Ross' solution with OP-41483, a PGI2 analogue, were compared after 12, 24, 36, and 48 hours. The viability of the preserved livers was assessed by measuring the tissue ATP concentrations and quantifying morphologic changes in the mitochondria observed by transmission electron microscopy using a 4-point scale, the mitochondrial score. A general trend towards progressive mitochondrial degeneration was observed in all groups. After 12 hrs of preservation, there was no significant difference between the groups. From 24 to 48 hours, the mitochondrial scores for livers preserved with OP-41483 were significantly higher than in the two other groups. No difference among the groups in tissue ATP concentration was observed at any time. Thus, OP-41483 was considered to retard mitochondrial degeneration in liver preservation by simple hypothermic immersion and does so by a mechanism not directly related to intracellular energy stores. The possibility that OP-41483 acts by stabilizing the lysosomal membrane is discussed.