A novel conception for liver preservation at a temperature just above freezing point.

BACKGROUND: It is generally accepted that 0 to 4 degreesC is a suitable temperature for organ preservation. The reason for this is based on the premise that at temperatures below 0 degreesC, intracellular ice is likely to form, with subsequent damage to cellular structures. However, it cannot be assumed that subzero temperatures will freeze the cell. In this study, we attempted to confirm the specific freezing point of rat liver and to preserve it at a temperature just above that point.
METHODS: Rat livers were stored for 24, 48, 72, and 96 h either at 4 degreesC (Group N) or at -0.8 degreesC (just above the temperature ascertained to be the specific freezing point of rat liver; Group H). After cold storage, the livers were perfused for 60 min using an isolated perfused liver model for assessment of liver function.
RESULTS: ATP and TAN (total adenine nucleotides) in reperfused liver tissues were significantly higher in Group H than in Group N for all preservation periods. ADP was significantly higher in Group H than in Group N for 24-, 72-, and 96-h preservation periods. Energy charge was significantly higher in Group H than in Group N for 24-, 48-, and 96-h preservation periods.
CONCLUSIONS: Regarding the content of ATP, ADP, and TAN and the adenylate energy charge, our results indicate that preservation at -0.8 degreesC is advantageous. This novel preservation technique seems to prolong the period that organs can be stored. Copyright 1999 Academic Press.