The effect of cell-free and erythrocyte-containing perfusion in rat livers

The isolated perfused rat liver (IPRL) has been used to evaluate various aspects of hepatic metabolism. However, varying perfusion compositions, specifically differing concentrations of erythrocytes (RBC), make comparisons difficult. We evaluated oxygen and glucose consumption, sodium and potassium release, and hepatic enzyme release in rat livers perfused with either cell-free (CF) or 10% RBC-containing perfusates for 90 min. Perfusate oxygen content and hepatic oxygen consumption were increased in RBC vs CF perfusion (VO₂ = 0.0208 ± 0.002 (RBC) vs 0.0107 ± 0.001 (CF) ml O₂/min/g). Glucose consumption was increased in CF perfusion (0.295 ± 0.048 (CF) vs 0.173 ± 0.065 (RBC) mg/min/g). Sodium, potassium, and alkaline phosphatase release were not increased in either CF or RBC perfusion. SGOT and SGPT release occurred in both perfusion systems, although significantly greater elevations were documented by 75 min in CF perfusion. Bile flow was significantly elevated with RBC perfusion. High-power light microscopy and electron microscopy documented more cellular and subcellular injury in CF perfusion. We conclude that perfusion with 10% RBCs is associated with less cellular injury and enhanced oxygen delivery to the isolated perfused rat liver.