Blood activities of hepatocellular enzymes such as lactate dehydrogenase (LDH), glutamic pyruvic transaminase (GPT) and glutamic oxalacetic transaminase (GOT) peaked at 12 hours after a single intraabdominal injection of ferric nitrilotriacetate (Fe3+-NTA) in rats. Enzymes such as alkaline phosphatase (ALP) and leucin amino peptidase (LAP) originating in the capillary bile ducts or bile secretory liver cells were also released into the blood between 6-24 hours after intraabdominal injection of Fe3+-NTA in rats. Furthermore, hyperoxidation of lipids occurred in rat hepatic cell membranes, reaching a peak 6 hours after intraabdominal injection of Fe3+-NTA. It was found that a single prior 0.5 Gy whole body X-ray irradiation significantly increased superoxide dismutase (SOD) activities and suppressed above-mentioned symptoms of transient hepatopathy in rats.