Objective:To study the function of angiogenin and other inflammatory mediators in rats with acute biliary pancreatitis (ABP). Methods:Seventy SD rats were randomly divided into the ABP group (n=56, ligating bile pancreatic duct) and the SO (sham operation, only flipped pancreas) group (n=14). The rats were sacrificed at 0, 6, 12, 24, 48, 72, and 120 hours after operation. The samples of blood serum and pancreas tissues were collected at each time point for detecting AMY, IL-10, TNF-α, NF-κB, Ang-1, Ang-2 levels using ELISA, pathological score and pancreatic moisture content. Results:The levels of AMY, IL-10, TNF-α,NF-κB at each time point in the ABP group were significantly higher than those in the SO group (P<0.05), and reached their peak value at 120 h during the observation period. The level of Ang-1 in the ABP group at 0 h decreased significantly(P<0.01), getting a little higher and remaining stable after 12 h. Ang-1 had no relationship with the severity of ABP. Ang-2 in the ABP group increased from 0 h, reaching its peak value at 48 h, and decreased at 72 h and 120 h. The level of Ang-2 in the ABP group was significantly higher than that in the SO group at each time point (P<0.01). Moreover, the level of Ang-2 was significantly positively correlated with ABP pathological score at the first 48 h (r=0.943, P<0.01), but the relationship was lost after 48 h. Similarly, the level of Ang-2 was also correlated with pancreatic moisture content during 12 h (r=0.830, P<0.01). Moreover, at first 6 h, pancreatic moisture content was significantly increased, which was corresponding to the decrease of Ang-1 and the increase of Ang-2. Conclusion:Inflammatory mediators play an important role in ABP. Ang-1 had no relationship with the severity of ABP. Elevated Ang-2 was significantly positively correlated with ABP pathological score and pancreatic moisture content in the early stage of ABP. Ang-2 may play a significant role in promoting vascular leak and proinflammatory effect in early stage of ABP, which indicates the severity of pancreatitis, or can be used to guide clinical treatment.