To investigate the effect of prostaglandin E_1 (PGE_1) on the liver function following laparotomy, 55 adult patients with normal liver function, undergoing elective laparotomy for gastric cancer under total intravenous anesthesia ,were randomly allocated to receiving intravenous infusion of PGE_1 at rate of 20 to 60ng?kg~(-1). min~(-1)(group PGE_(1,n)=27), or normal saline (group control, n=28 )from the opening of abdomen to the end of operation,respectively. The serum concentrations of glutamin-pyruvic transaminase (GPT)and glutamic-oxaloacetic transaminase (GOT)were measured postoperatively. The results showed that as compared with the values before the operation,the levels of GPT and GOT increased significantly in both groups on the first postoperative day (P