Abstract： Objective To investigate the effect of jejunal casein perfusion on pancreatic exocrine secretion in experimental acute necrotic pancreatitis (ANP) rats and analyze the neuromechanism that may be involved. Methods 30 SD rats were randomly divided into three groups (control group, ANP group and ANP jejunal nutrition group). Experimental ANP was induced by intra pancreatic duct injection of sodium taurocholate (STC). Animals in ANP jejunal nutrition group were given jejunal casein perfusion 24h after model induction, while control group and ANP group received jejunal saline perfusion. Pancreatic juice was collected every 15 min for six times and the volume of pancreatic juice and protein in pancreatic juice were detected. After jejunal nutrition c-Fos expression in nucleus tractus solitarii (NTS) was determined by immunohistochemistry method in three groups. Results There was no significant difference between the volume of pancreatic juice at different time points in ANP group and ANP jejunal nutrition group, however, these parameters were significantly lower than that of control group (P < 0. 05). There was no significant difference among the 3 groups in the protein level in the pancreatic juice during jejunal nutrition infusion, however, during the periods of 0 ～ 15 min, 15 ～30 min, 30 ～45 min and 75 ～90 min, the protein levels in the pancreatic juice in ANP and ANP jejunal nutrition group were lower than that of control group (P < 0.05). After jejunal perfusion, c-Fos expression was found in ANP jejunal nutrition group but not found in ANP and control groups. Conclusions Jejunal casein perfusion enhanced NTS c-Fos expression, but did not increase the volume of pancreatic juice and protein.