[The impact of dietary methionine-restriction on tight junction expression and function in a rat colonitis model].

Objective: To study the impact of methionine restriction (MetR) on mucosal histopathology, permeability and tight junction composition in a dextran sulfate sodium (DSS)-induced colitis model, and to explore its underlying mechanism.

Methods: SD rats were randomly divided into 4 groups: normal rats fed by a complete amino acid (AA group) diet, normal rats fed by MetR diet (MetR group), DSS treated rats fed by a complete amino acid (DSS+AA group) and DSS treated rats fed by MetR diet (DSS+MetR group), each group had 15 rats.Abdominal aorta blood sampling was taken at day 21 after DSS model been established to analyze blood routine examination, liver and kidney function and level of electrolyte.

[Changes in tight junction protein expression and permeability of colon mucosa in rats with dextran sulfate sodium-induced inflammatory bowel disease].

Objective: To develop an experimental rat model of inflammatory bowel disease (IBD) by administration of dextran sulfate sodium (DSS), and to observe changes in the tight junction protein expression and permeability of colon mucosa.

Methods: Male Sprague-Dawley (SD) rats were randomly divided into control (n=27) and IBD model groups (n=27). In the IBD model group, IBD was induced by 6-day administration of 3% DSS in water followed by 14-day administration of water only.