Taurine Reduces Experimental Liver Injury after Cold Ischemic Preservation and a Period of Rewarming Prior to Reperfusion

Abstract

Livers of male Wistar rats (250–300 g) were isolated and flushed with 10 ml of Ringer’s solution and 10 ml of UW preservation solution. Then the organs were stored for 24 h at 4°C in UW solution. Livers of Group 1 were rinsed with 10 ml of Ringer’s solution and reperfused after hypothermic storage with oxygenated Krebs-Henseleit solution (95% O₂; 5% CO₂) in a nonrecirculating system at constant pressure (10 mmHg) and 37°C.

Livers of Group 2 were incubated for 30 min at 37°C prior to reperfusion, in order to simulate rewarming of the organ upon surgical implantation. Livers of Group 3 were treated like Group 2, but taurine was admixed to the UW solution (1 mM).

Livers of Group 1 showed little signs of a preservation/reperfusion injury, with low enzyme activities of the parenchymal ALT and endothelial purine nucleoside phosphorylase (PNP) in the postischemic rinse solution (ALT: 19.9 ± 12.4; PNP: 3.3 ± 0.4 U/liter), adequate portal flow values about 3 ml/g/min and high O₂ uptake at the end of the experiment (VO₂: 3.2 α 0.4 ml/100g/min). Livers of Group 2 exhibited nearly tenfold higher enzyme activities in the rinse solution (ALT: 247.0 α 94.7*; PNP: 29.5 α 17.0* U/1) and disturbed tissue perfusion with significantly reduced flow values of about 2 ml/g/min during the first 10 min of reperfusion. As a result, the recovery of O₂ uptake was only 2.2 α 0.3 ml/100 g/min*.

Addition of taurine (Group 3) resulted in a significant reduction of the enzyme loss (ALT: 96.2 α 50.0#; PNP: 12.4 α 7.0# U/liter) and improved portal flow values and O₂ uptake at the end of reperfusion (2.7 α 0.3 ml/100 g/min#). The results give evidence for the importance of the rewarming period after hypothermic storage, which is inevitable during implantation of the organ in vivo. Taurine seems to exert a protective effect, affecting both the vascular endothelium and parenchymal tissue (*p< 0.05 vs Group 1; # p< 0.05 vs Group 2).