A rapid, simple, and cost-effective method for screening liver preservation solutions in the rat

Rat liver transplantation models or isolated liver perfusion models are currently used for assessing efficacy of liver preservation methods. We tested the hypothesis that hepatocellular enzymes released into the washout solution after preservation may predict hepatic function during reperfusion and could thus be alternatively used for evaluating efficiency of liver preservation solutions. Furthermore, we applied this approach for assessing the role of Kupffer cells (KC) in preservation-induced liver damage.

After preservation in University of Wisconsin (UW) or Euro-Collins (EC) solution, rat livers were washed with Ringer-lactate solution. Correlations between enzymes released into the washout solution and hepatocyte functional parameters determined during reperfusion on using a blood-free perfusion model were investigated.

In UW-preserved livers, acid phosphatase (ACP) activity correlated negatively with bile flow (R = -0.904), taurocholate intrinsic clearance (R = -0.841), and bromosulfophthalein excretion (R = -0.831). Both alanine transaminase and aspartate transaminase activities correlated with the functional parameters investigated. In EC-stored livers, correlation was also found between ACP activity and bile flow (R = -0.666). Livers stored in UW solution exhibited approximately 3 times lower washout activities of enzymes studied than livers stored in EC solution. Mitochondria isolated from UW-stored livers exhibited significantly better function than those isolated from EC-stored livers. Blockade of KC did not influence enzyme release into the washout solution.

Determination of ACP, alanine transaminase, and aspartate transaminase activities in the washout solution can be used as a rapid, simple, and cost-effective way for screening liver preservation solutions. The results also suggest that KC were not involved in preservation-induced liver damage.