The effect of perfusion speed on graft reperfusion injury after rat orthotopic liver transplantation.

Objective. The objective of this study was to investigate the effects of various perfusion speeds on reperfusion injury of grafts after liver transplantation. Methods. Liver transplantation was performed from Sprague-Dawley (SD) to SD rats. Recipients were divided into 4 groups according to perfusion speed: 50 mL/h for group A, 100 mL/h for group B, 150 mL/h for group C, and 200 mL/h for group D. Peripheral blood was collected from the caudal vein. All survivors were humanely killed at 24 hours posttransplantation. The morphological changes in grafts were evaluated using light microscopy, serum tumor necrosis factor-alpha (TNF-alpha), and endothelial nitric oxide synthase (eNOS) proteins as well as their messenger RNA (mRNA)-intragraft levels. Results. The pathohistological damage of grafts in the 150 mL/h and 200 mL/h groups were compared with the 50 mL/h and 100 mL/h groups. TNF-alpha in serum was increased at 6 hours, reaching a peak at 12 hours posttransplantation. The TNF-alpha levels in the 50 mL/h and 100 mL/h groups were significantly lower than the 150 mL/h and 200 mL/h groups; the 50 mL/h group was greater than the 100 mL/h group as well as the 200 mL/h group was greater than the 150 mL/h group. The expressions of eNOS protein and mRNA intragraft in the 150 mL/h and 200 mL/h groups were significantly reduced compared with the 50 mL/h and 100 mL/h groups, and the 50 mL/h group was decreased when compared with the 100 mL/h group. There was no significant difference between the 150 mL/h group and the 200 mL/h group. Conclusion. The optimal perfusion speed for harvesting rat liver graft is 100 mL/h. High-speed perfusion may impair sinusoid endothelial cells and low-speed perfusion may extend the warm ischemia time and increase microthrombus formation.