Obiective lt;brgt;To investigate the change of the activity of proliferation in cultivated Muuml;ller cells treated by advanced glycation endoproducts (AGEs), and the effect of these changes on expression of occludin in bovine retinal vascular endothelial cells (BREC). lt;brgt;Methods lt;brgt;The cultivated Muuml;ller cells were devided into normal growth group and cultured with AGEs group. The cultured BREC were devided into 4 groups:group 1, without any medium; group 2, with normal growth Muuml;ller cell medium (MCM); group 3,MCM treated by AGEs; group 4, without cell as the control. Enzyme-linked immuno sorbent assay was used to detect the content of occludin in the medium in the 4 groups. lt;brgt;Results lt;brgt;The content of expression of occludin was the most in group 2, less in group 1, and the least in group 3. lt;brgt;Conclusion lt;brgt;AGEs may promote the abnormal proliferation of Muuml;ller cells and inhibit the expression of occludin in BREC. lt;brgt;(Chin J Ocul Fundus Dis, 2006, 22: 28-30)
ObjectiveTo explore the mechanism of liver capillary permeability in rats with severe acute pancreatitis (SAP). MethodsTotally 40 healthy Sprague-Dawley (SD) rats were randomly divided into two groups: sham operation (SO) group and SAP group, SAP group were divided into four subgroups according to sampling time (3 h， 6 h, 12 h， and 24 h). The model was established by injecting 5% sodium taurocholate retrogradely into pancreaticobiliary ducts. The changes of tumor necrosis factor-α (TNF-α), pathohistology, and tissue moisture content were compared among different groups. Liver occludin protein expression was analyzed by immunohistochemistry method, and occludin mRNA was measured by RT-PCR. ResultsThere was no significant pathological changes of liver tissue in the SO group. Typical pathological changes of SAP， such as interstitial edema, vasodilatation, infiltration of inflammatory cells, were found in the SAP group. TNF-α level and tissue moisture content of each phase increased gradually, and the highest level appeared at 24 h within the observing period. The two above indicators at different time point in subgroups were significantly different from each other and higher than those in the SO group (Plt;0.05)． In the SAP group, the expression of occludin and it’s mRNA began to decrease at 3 h to the bottom at 6 h and rebounced significantly at 12 h, 24 h compared with those at 6 h (Plt;0.05), but still lower than those in the SO group (Plt;0.05). ConclusionUpregulation in TNF-α and subsequent downregulation in occludin protein and mRNA maybe bly related to the severe liver capillary permeability in rats with SAP.
Objective To investigate the effects and mechanisms of bile on small intestine mucosal barrier.Methods Fifty Wistar rats were assinged into 3 groups randomly: obstructive jaundice (OJ) group （n=20）, biliary external drainage group （n=20） and control group （n=10）. Ten days after operation, the plasma endotoxin level was determinated, the terminal ileum mucosas was obtained to be morphologically measured by light microscope, and immunohistochemistry and Western blot were uesd to examine the expressions of tight junction proteins zona occludens-1 (ZO-1) and occludin in the mucosas. Results Atrophy significantly appeared in the distal ileum mucosas in OJ group. Compared with control group, the intestinal villus height, mucosa thickness and crypt depth in OJ group were obviously decreased 27.8%, 21.7%, and 25.4% (P=0.001, 0.001, 0.040). There were no differences between external drainage group and control group (P=0.050, 0.070, 0.080); While the values of external drainage group were significantly higher than those in OJ group (all P=0.001). The level of plasma endotoxin was up to (1.49±0.27) EU/ml in OJ group compared with control group 〔（0.27±0.09） EU/ml〕, P=0.001. In external drainage group, the value was （0.91±0.25） EU/ml, which was obviously higher than that in control group and lower than that in OJ group （all P=0.001）. Immunohistochemical study showed b positive expression of ZO-1 dropped from 7/10 in the control group to 6/20 in OJ group （P=0.040）, occludin expression was 8/10 in control group and 7/20 in OJ Group （P=0.020）; expressions of them in external drainage group 〔8/20 （P=0.100,0.210） and 9/20 （P=0.060, 0.200）〕 displayed no significant differences compared with the other twogroups. Quantitative testing of Western blot showed the expressions of ZO-1 and occludin in OJ group were significantly lower than those in control group (P=0.001, 0.010), the values in external drainage group were higher than those in OJ group （P=0.005, 0.014）. The expression of ZO-1 was lower in external drainage group than that in control group (P=0.001), and there was no significant difference of occludin between the two groups (P=0.062）. Conclusion Lack of intestinal bile will undermine the intestinal tight junction protein composition, and make intestinal mucosal barrier impaired. The intestinal barrier more severely injured when biliary tract obstructs because of multiple factors. Bile plays an important role in the maintenance of intestinal mucosal barrier.