Study of the protective effects of dexamethasone on ileum mucosa injury in rats with severe acute pancreatitis.

Objectives: To study the protecting effects of dexamethasone on ileum mucosa injury of rats with severe acute pancreatitis (SAP).

Methods: The SAP rats were prepared by improved Aho's methods. The plasma endotoxin and inflammatory mediators in serum were determined. The rat mortality, pathological changes of terminal ileum, nuclear factor kappa B (NF-kappaB), apoptotic indexes, and apoptotic related protein expression were observed.

Results: The plasma endotoxin, inflammatory mediators, and NF-kappaB protein expression as well as pathological scores of the treatment group of ileum mucosa were lower than those of the model group at different time points. P selectin in model group significantly exceeded the dexamethasone treatment group at 3 and 6 hours (P < 0.01, P < 0.05). Caspase-3 protein expression in dexamethasone treatment group significantly exceeded the model group at 3 and 6 hours (P < 0.05), and apoptotic indexes were higher than those of the model group at 6 hours (P < 0.05), but Bax protein has shown no marked difference among groups.

Conclusions: Dexamethasone can reduce the endotoxin level and inflammatory mediators and down-regulate NF-kappaB protein expression of ileum mucosa, and ileum mucosa epithelial cell apoptosis induction was involved as well. The tissue microarrays technique is of advantage in SAP study.