Effect of ischemic preconditioning on hepatic tolerance to cold ischemia in the rat

A short warm ischemia before reperfusion has been shown to improve the tolerance of the heart and the liver to a prolonged warm ischaemia. The present experimental study was conducted to evaluate the effect of such preconditioning on hepatic tolerance to an extended cold ischemia. In a model of isolated perfused liver, livers from Wistar rats (250-350 g) were stored for 24 h in UW (4 degrees C) immediately after harvesting and reperfused for 3 h at 37 degrees C. Control livers subjected to a 24-h cold ischemia were compared to livers subjected to preconditioning (defined as a 5- or 10-min clamping of the hepatic pedicle followed by a 10-min reperfusion before liver harvesting) prior to the definitive 24-h cold ischemia. While there was no difference in bile production between the preconditioned groups and the controls, transaminases and LDH release was significantly increased, vascular resistance was enhanced, and preservation injury was more extensive in both preconditioned groups as compared to controls. In contrast to the beneficial effect reported on prolonged warm ischaemia, preconditioning has a deleterious effect on hepatic tolerance to an extended cold ischemia.