Background Terminal ileitis (TI) is an inflammatory condition of the distal portion of the ileum. Objective To investigate the changes and significance of neurotensin (NT) in the course of experimental terminal ileitis (ETI). Methods A total of 90 Sprague Dawley (SD) rats were randomly divided into the control, model, and suture groups (30 rats in each group). After 2, 4, and 8 weeks of surgery, 10 TI tissues were taken for endoscopic observation in each group. Hematoxylin-eosin (HE) staining was used to detect the pathological changes. The NT levels in serum and terminal ileum mucosa were detected by Enzyme-linked immunosorbent assay (ELISA). Results Acute inflammatory changes were observed in the suture and the model groups after 2-week of operation. At 4 weeks, compared to the control group, the inflammatory damage in the model group became heavier, but it was reduced in the suture group. At 8 weeks, the model group showed chronic inflammation. However, there was no obvious inflammatory cell infiltration in both the suture group and control group. NT levels were increased in the suture and model groups at 2 weeks, particularly in the model group, and they were significantly higher in the suture and model groups than those in the control group ( P < 0.05). At 4 weeks, the NT levels in the model group continued to rise, while they decreased in the suture group ( P < 0.05). After 8 weeks, NT levels in the model group were significantly higher than those in the suture and control groups ( P < 0.05). Furthermore, from 2 weeks to 8 weeks, the NT concentration in the model group gradually increased, and the suture group increased for 2 weeks, followed by a downward trend. Conclusions In the ETI, the changes in NT concentration in serum and TI mucosa were positively correlated with the degree of inflammation.
