OBJECTIVE This study was conducted to evaluate the association of tumor necrosis factor-a and soluble receptors as known antagonists in liver surgery with regard to ischemia and reperfusion. METHODS Preoperative and perioperative changes of TNF, soluble TNF receptor I and II as well as IL-6 were evaluated in twelve patients with partial liver resection. Before liver ischemia and after reperfusion, the levels were measured in the portal and hepatic vein, as well as systemically. Ten patients with gastrectomy and lymphadenectomy as another major abdominal operation and eight healthy volunteers served as the control groups. RESULTS Uncomplicated liver resections were associated with a prolonged and significantly increased release of soluble receptors until the third (for soluble receptor I) or the fifth postoperative day (for soluble receptor II). No tumor necrosis factor immunoreactivity could be detected, except in one patient with postoperative sepsis. The pattern of interleukin-6 immunoreactivity during liver resection was characterized by a delayed peak on day 2 (p<0.01 vs preop), compared to an early peak after 8 hours in control patients undergoing gastrectomy (p<0.05 vs preop). Liver resection elicits a release of interleukin-6 and soluble receptors without ischemia/reperfusion-induced effects. A strong correlation of the soluble receptors with interleukin-6 (p<0.01) could be detected in liver resection and gastrectomy. CONCLUSIONS Uncomplicated liver resections were associated with a prolonged and increased release of soluble tumor necrosis factor receptors while no immunoreactivity could be detected. The strong correlation of soluble receptors with interleukin-6 may suggest an important role in the acute phase response of major operations.