Harvesting trauma to the graft dramatically decreases survival after liver transplantation. Since activated Kupffer cells play a role in primary nonfunction, the purpose of this study was to test the hypothesis that organ manipulation activates Kupffer cells. To mimic what occurs with donor hepatectomy, livers from Sprague-Dawley rats underwent dissection with or without gentle organ manipulation in a standardized manner in situ. Perfused livers exhibited normal values for O₂ uptake (105 ± 5 µmol · g¹ · h¹) measured polarigraphically; however, 2 h after organ manipulation, values increased significantly to 160 ± 8 µmol · g¹ · h¹ and binding of pimonidazole, a hypoxia marker, increased about threefold (P < 0.05). Moreover, Kupffer cells from manipulated livers produced three- to fourfold more tumor necrosis factor- and PGE₂, whereas intracellular calcium concentration increased twofold after lipopolysaccharide compared with unmanipulated controls (P < 0.05). Gadolinium chloride and glycine prevented both activation of Kupffer cells and effects of organ manipulation. Furthermore, indomethacin given 1 h before manipulation prevented the hypermetabolic state, hypoxia, depletion of glycogen, and release of PGE₂ from Kupffer cells. These data indicate that gentle organ manipulation during surgery activates Kupffer cells, leading to metabolic changes dependent on PGE₂ from Kupffer cells, which most likely impairs liver function. Thus modulation of Kupffer cell function before organ harvest could be beneficial in human liver transplantation and surgery.