动物造模,肠道菌群 z-bio 2022-02-09 366

　　OBJECTIVE: To discuss the effect of dexamethasone pollution in the water environment on the intestinal flora of mice.

　　Method: 20 Balb/c mice were randomly divided into control group and experimental group, with 5 mice in each group. The experimental low-dose group was fed drinking water containing 0.035 ng of dexamethasone sodium phosphate, the middle-dose group was 0.225 ng, the high-dose group was 2.25 ng, and the control group was fed drinking water without dexamethasone sodium phosphate. Changes in mouse behavior, fur, stool, etc. were observed daily. On the 36th day, the mice were sacrificed, and the blind tissue was retrieved to extract bacterial genomic DNA. The 16S rDNA V6 variable region was amplified, and the amplified products were analyzed by denaturing gel gradient electrophoresis (DGGE). The dominant bands on the DGGE map were excised, cloned and sequenced after amplification and purification, and their sequences were compared and analyzed by BLAST.

　　RESULTS: The mice in each experimental group showed signs of irritability, fighting and biting their tails. The cluster analysis of DGGE map showed that the ileocecal region of mice in each group had a relatively stable flora; the principal component analysis showed that there were certain differences in the dominant flora of each group; the analysis of bacterial flora diversity showed that compared with the control group, the low-dose The variety and quantity of flora in the group increased significantly (P<0.05); the variety and quantity of the medium and high dose groups increased significantly (P<0.01). Sequence analysis of 16S rDNA V6 region showed that the experimental group and the control group had 15 common bacterial genera and 2 different bacterial genera, and the dominant bacterial species and proportion were changed. The control group was colonized with bacteria of the genus Lactobacillus, while the bacteria of the genus Lactobacillus disappeared in the medium and high dose experimental groups, but bacteria of the genus Shigella appeared.

　　CONCLUSION: Dexamethasone pollution in drinking water can affect the nervous system of mice, change the variety, quantity and proportion of dominant bacteria in the intestinal tract of mice, and increase the diversity of flora; inhibit the colonization of intestinal probiotics, which is beneficial to the intestinal tract. Invasion of pathogenic bacteria.