Background: Prostaglandin E-1 (PGE(1)) has protective effects experimentally and clinically in individual models of hepatic ischaemia-reperfusion injury and of partial hepatectomy. The present study investigated the effects of intraportal administration of PGE(1) on hepatic blood flow, systemic arterial pressure and long-term animal survival after 60 min of total liver ischaemia followed by 70 per cent partial hepatectomy in rats. Methods: Total liver ischaemia tvas induced by occluding the hepatoduodenal ligament for 60 min. PGE(1) 0.5 mu g per kg per min was infused intraportally for 15 min. before inducing ischaemia and for 120 min after ischaemia in the treatment group. Normal saline was infused in the control group. During ischaemia 70 per cent partial hepatectomy was performed. Portal venous dow (PVF), peripheral tissue blood flow (PTBF) and hepatic artery how were measured before and after ischaemia. Serum biochemical analysis was carried out at 1, 3 and 24h, and 7 and 14 days; and liver histology at 1 and 24h, and 7 days after reperfusion. Survival was followed for 1 year. Results: Intraportal infusion of PGE(1) significantly improved PVF and PTBF without affecting the systemic arterial pressure. Long-term survival was significantly higher in the PGE(1) group. Serum aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase levels decreased significantly, and 2-h bile flow was significantly improved, in the PGE(1) group. Histological examination revealed significant portal venous congestion, sinusoidal congestion, fatty degeneration and tissue necrosis 24h and 7 days after reperfusion in the control group. Conclusion: PGE(1) has a protective effect against liver damage when the liver is injured by warm ischaemia and reperfusion followed by partial resection.