A fish oil diet minimizes hepatic reperfusion injury in the low-flow, reflow liver perfusion model

Abstract

In this study, the effects of fish oil treatment on hepatic reperfusion injury in a low-flow, reflow perfusion model were investigated. Rats were fed powdered diets containing either 5% corn or 5% encapsulated fish oil for 13 to 15 days. Average daily food intake in both control and fish oil groups was about 20 g per rat, and weight gain averaged 9 g/rat/d. Livers were perfused at flow rates around 1 muL/g/min for 75 minutes, which caused cells in pericentral regions to become anoxic because of insufficient delivery of oxygen. When normal flow rates (about 4 mL/g/min) were restored for 40 minutes, reperfusion injury occurred. Upon reflow, lactate dehydrogenase (LDH) release increased from basal levels around 1 to 50 IU/g/h in livers from control rats, whereas fish oil treatment minimized values to 16 IU/g/h Rates of bile production reached 23 muL/g/h during reperfusion in livers from controls and 38 muL/g/h in the fish oil-treated group. Oxygen uptake was about 110 mumol/g/h during the reperfusion period in livers from both groups. Malondialdehyde (MDA), an end product of lipid peroxidation, was released into the effluent perfusate at rates around 80 nmol/g/h during reperfusion in controls, and values were not affected by fish oil treatment, Portal pressure, an indicator of hepatic microcirculation, increased from basal levels of 3 to 10.5 cm H2O during reperfusion in controls, but was only elevated to 8.3 cm H2O in the fish oil-treated group. In addition, Trypan Blue distribution time, another indicator of hepatic microcirculation, was reduced significantly by 44% by fish oil treatment.(ABSTRACT TRUNCATED AT 250 WORDS)