动物造模,高原急性缺氧肠道应激损伤 zi-bio 2024-03-13 854

　　Objective: To establish an experimental high-altitude mouse intestinal stress injury model by simulating an acute hypoxic environment, laying a foundation for exploring the pathogenic mechanism and prevention and treatment measures of high-altitude acute gastrointestinal diseases.

　　Method: According to body weight, 36 SPF grade adult male BALB/c mice were randomly divided into a 24 hour normoxic group, a 72 hour normoxic group, a 24 hour hypoxic group, and a 72 hour hypoxic group, with 9 mice in each group. The normoxic control group mice were raised in a conventional barrier environment; The hypoxic stress group was raised in a low oxygen chamber in a barrier environment, with an oxygen concentration set at 10% to simulate a high-altitude environment. They were subjected to 24 and 72 hours of stress, respectively, to establish an acute hypoxia induced intestinal injury model. After the modeling was completed, the mice were weighed and anesthetized with 1% pentobarbital sodium. The necks of each group of mice were cut off and euthanized. Duodenal and colon tissues were collected and HE staining was performed to observe the pathological morphology of the intestinal tissue. The expression levels of tight junction related proteins in the intestinal tissue were detected by protein blotting and immunohistochemistry. The mRNA expression levels of inflammatory cytokines and chemokines were detected by real-time fluorescence quantitative PCR. TUNEL staining was used to detect indicators such as apoptosis activity of intestinal epithelial cells, in order to evaluate the intestinal injury related phenotype of the model.

　　Compared with the normoxic group, the mice in the 24 hour and 72 hour hypoxic groups showed weight loss, shortened duodenal villus length, abnormal crypt structure, decreased villus/crypt ratio, inflammatory cell infiltration in the colon mucosa, and irregular crypt structure. The expression levels of Occludin and Zonula occludens-1 (ZO-1) in the duodenum and colon tissues of mice in the 24 hour and 72 hour hypoxic groups were significantly reduced (P<0.05), while the expression of pro apoptotic protein Bax was significantly upregulated and the expression of anti apoptotic protein Bcl-2 was significantly downregulated (P<0.05). In addition, the apoptotic activity of intestinal epithelial cells was significantly enhanced (P<0.05). In addition, after 24 and 72 hours of hypoxic stress, interleukin-1 (IL-1) was found in the duodenal tissue of mice β、 IL-6, monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor- α (tumour crossing factor)- α， TNF- α） The mRNA level significantly increased (P<0.05); Hypoxia stress 24 p=">0.05"; However, after 72 hours of hypoxic stress, pro-inflammatory factor IL-1 was found in the colon tissue of mice β、 TNF- α、 The mRNA levels of IL-6, MCP-1, and anti-inflammatory factor IL-10 were significantly increased (P<0.05).

　　Conclusion: Using a low oxygen chamber to simulate an acute hypoxic environment at high altitude can lead to stress in the intestinal tissue of mice