The Expression Of Occludin Protein In Intestinal Epithelium Of Severe Acute Pancreatitis Mice

ObjectiveTo observe the expression changes of occludin protein in intestinal epithelium of severe acute pancreatitis mice and investigate the relationship between occludin and intestinal mucosal barrier damage preliminary.Materials and Methods40 male Kunming mice (weighing 20-25g) were randomly divided into control group(n=8), experimental group(n=32). The experimental group was divided four time point(3,6,12,24h). The experimental group mice were intraperitoneal injected with L-arginine (250mg/g body weight) for 2 times with an interval of 1 hour,8 mice in the experimental group were randomly killed at 3,6,12,24 hours after last injection. Control group's mice were injected with the same volume of 0.9% sodium chloride in the same way and were sacrificed at the end of last injection. The pancreas and ileum of mice were removed rapidly. Pancreatic tissue were stained by HE and observed under microscope. Observed ultrastructural changes of intestinal epithelial cells under electron microscope and determined expression of intestinal epithelial cells tight junction protein occludin.ResultThe control group's ultrastructure of intestinal epithelium cells showed normal under electron microscope. In the experimental group, there were no changes at 3h,but intestinal epithelial cells of 6,12,24h time point, microvilli were thin, rare or disrupt and shed, the organelles were damaged, nuclear's heterochromatin condensed and obviously gathered around, cell juctions became widen, these phenomenons became most obvious at 24 hours. Occludin protein uniformly distributed top of the intestinal epithelial cells junctions in control group, but the experimental group's occludin uneven distributed and decreased gradually, reached to a minimum at 24 hours. The average optical density of each group were 0.3448±0.0028,0.3431±0.0020,3423±0.0019, 0.3394±0.0015,0.3095±0.0027. There is no statistical significance between control group and 3h (P>0.05), but have statistical significance compared with 6h,12h and 24h (6h vs control group P<0.05; 12h vs control group P<0.01,24h vs control group P<0.01·)ConclusionsIntestinal mucosal barrier was injured in the early stage of severe acute pancreatitis in mice, The reduction of occludin expression lead to wide cell's junction and damage the intestinal mucosal barrier.