Autonomic nervous system and gut-derived endotoxin: Involvement in activation of Kupffer cells after in situ organ manipulation

Gentle in situ organ manipulation rapidly causes disturbances in the hepati c microcirculation, hypoxia, and activation of Kupffer cells, Because the m echanisms of Kupffer cell activation after organ manipulation remain unclea r, the possible role of the autonomic nervous system and gut-derived endoto xin were assessed. To mimic what occurs with major abdominal surgery, liver s from female Sprague Dawley rats (200-230 g) underwent minimal dissection for 12 minutes and were manipulated gently or were left alone for 13 subseq uent minutes. Kupffer cells were activated 2 hours after manipulation, refl ected by a significant increase in intracellular calcium ([Ca2+](i)) from a bout 90 nM in unmanipulated controls to more than 180 nM in response to lip opolysaccharide (LPS 100 ng/ml), Furthermore, IiupBr cells from manipulated rats produced about threefold more tumor necrosis factor-cr after LPS (100 ng;ml! than did the unmanipulated controls. h Ioreover, 0, uptake of es si tu perfused liver was increased from about 110 mu mol/g/hr in unmanipulated controls to more than 160 mu mol/g/hr 2 hours after organ manipulation. Bi nding of pimonidazole (120 mg/kg IV), a 2-nitroimidazole hypoxia marker giv en 2 hours after manipulation, increased about 2.5 fold, and hepatic glycog en was depleted. Two hours after organ manipulation gut permeability to hor seradish peroxidase was elevated and endotoxin in the portal venous blood w as increased twofold. Microsurgical hepatic denervation, ganglionic blockad e, adrenalectomy, and antibiotics to sterilize the gut before manipulation prevented activation of Kupffer cells by organ manipulation, Hexamethonium and adrenalectomy prevented increases in gut permeability caused bf manipul ation. Although antibiotics blunted the increase in portal venous endotoxin significantly, there was no effect oil gut permeability;. These data indic ate for the first time that both the autonomic nervous system and gut-deriv ed endotoxin are involved in activation of Kupffer cells after organ manipu lation.