We analysed superoxide anion (O2-) release from primary-cultured human hepatic macrophages (HHM phi) and peripheral blood monocytes (MO) derived from patients with normal and cirrhotic livers. Primary cultured human hepatic macrophages and MO from cirrhotic patients released less O2- than cells from normal patients. Superoxide anion release by HHM phi showed a significant, positive correlation with the serum glutamate pyruvate transaminase (GPT) level, whereas O2- release by MO showed only a weak correlation with the GPT level. In conclusion, a significant reduction in O2- release was observed in HHM phi and MO cultured from cirrhotic patients. Primary-cultured human hepatic macrophages are probably more susceptible to environmental changes within the cirrhotic liver than MO, since they are found locally within the liver and correlate with serum GPT levels.