动物造模,微生物菌群 z-bio 2021-02-19 317

　　Objective: To analyze the effects of unpredictable stress stimulation on the immune system of the gastrointestinal tract and microbial population by observing the rats after 9 days of intervention with unpredictable stress stimulation, and to provide reference materials for the study of chronic stress on gastrointestinal function .

　　 Method: 24 SD rats were randomly divided into a blank group and a chronic stress model group. The rats in the model group received unexpected stress stimulation for 9 consecutive days. After modeling, 5 rats were randomly selected from the normal and model groups, and stool samples were collected to analyze the diversity of intestinal flora. Among 12 rats in each group, 4 rats were randomly selected for perfusion fixation, and gastric antrum and colon tissues were collected for morphological observation. The plasma and adrenal tissues of the remaining 8 rats were collected to detect corticosterone content.

　　 Results: (1) After 9 days of unpredictable stress stimulation, the weight gain of rats in the model group was significantly lower than that in the normal group (P = 0.001), while the increase in corticosterone was 9 days later. The adrenal cortex level of the model group was higher than that of the normal group, but was significantly lower than that of the rats (P = 0.006). The plasma adrenocortical hormone content of the model group was compared with that of the normal group. Increase (P = 0.025). (2) After 9 days, the arrangement of epithelial cells in the gastric mucosa of the model group was sparser than that of the normal group, and the thickness was less than that of the normal group (P = 0.034). The number of neutrophils. The gastric lamina propria of the model group was lower than that of the normal group, but less than the normal group (P = 0.016). The number of neutrophils in the colonic mucosa of the model group was higher than that of the normal group. Group (P = 0.013). 3) After 9 days of chronic unpredictable stress, α diversity analysis showed that compared with the normal rat group, the OTU bacterial species in the stool samples of the model group increased significantly (P = 0.001). Compared with the normal group, the ratio of Desulfovibrio to Helicobacter pylori in the rat samples of the model group increased (P = 0.011, P = 0.047). Compared with the normal group, the content of Bacteroides in the rat samples of the model group was significantly reduced. A group of mice. The difference is statistically significant (P = 0.001).

　　 Conclusion: Unpredictable stress stimulation may create a stable chronic stress rat model. The immunosuppression caused by chronic stress is related to the imbalance of the intestinal flora of rats.