['Ethanol is involved in approximately 40% of the cases of acute pancreatitis.', 'To investigate the influence of ethanol on the pancreatic generation of oxygen-free radicals (OFR) in alcohol-induced acute pancreatitis as one possible pathway of proenzyme activation in this disease.', 'In one model of acute pancreatitis, the combination of ethanol with mild stimulation of the pancreas and short-term duct obstruction leads to acute pancreatitis within 24 hours. Pancreatic tissue and blood samples were assessed for reduced (GSH) and oxidized (GSSG) glutathione, malondialdehyde, conjugated dienes (CD), and myeloperoxidase. The histologic development of the acute pancreatitis was followed between 0.5 and 24 hours.', 'Ethanol systemically decreased the radical defense system (GSSG: control 0.49 +/- 0.58, ethanol 2.76 +/- 1.44, p < 0.001; GSH: control 10.13 +/- 4.45, ethanol 9.52 +/- 3.43, p < 0.05). In the pancreas, oxygen free radicals also led to membrane peroxidation (CD: control 3.70 +/- 1.67, ethanol 6.10 +/- 2.15, p < 0.05). When alcoholic pancreatitis was induced, the level of oxygen radicals further increased (GSSG: control 0.17 +/- 0.15, ethanol 0.27 +/- 0.17, p < 0.005, pancreatitis 0.42 +/- 0.29).'] Does oxygen radical production precede alcohol-induced acute pancreatitis in rats?