Portal circulation and the function of hepatocytes during ex vivo perfusion of the rat liver preserved for six hours after core cooling.

Portal circulation and the function of hepatocytes during isolated organ perfusion were compared between the rat liver perfused immediately after extirpation and the liver perfused after core cooling and six hours of preservation. Nine rat livers were extirpated after core cooling, preserved for six hours in University of Wisconsin (UW) solution at 4 degrees C and then were connected to a perfusion chamber (hypothermic preservation group: 6-hr HP group). Six rat livers were immediately connected to the perfusion chamber after extirpation (control group). During 60 minutes of isolated liver perfusion, both portal circulation and the function of hepatocytes were determined every 10 minutes. Portal vein resistance increased and portal blood flow decreased during the first 20 minutes of perfusion and then stabilized in both groups. Portal vein resistance was significantly higher and portal blood flow was significantly lower for the first 10 minutes of perfusion in the 6-hr HP group, compared to the control group. The function of hepatocytes, determined by the rate of elimination of ammonia, oxygen consumption, and glucose availability were depressed in the 6-hr HP group, compared to the control groups during isolated liver perfusion. However, there was no statistically significant difference of portal perfusion and the function of hepatocytes between the two groups at the end of perfusion. The results of the present study indicate that the rat liver can be preserved in a satisfactory condition for six hours by the use of hypothermic preservation, coupled with core cooling.