ABSTRACT
OBJECTIVE@#To discuss the changes in the tight junction protein of intestinal epithelium and permeability of colonic mucosa and its possible mechanism by building the rat mode of inflammatory bowel disease at the chronic recovery stage.@*METHODS@#A total of 36 SD rats were divided into the model group and control one according to the random number table, with 18 rats in each group. Rats in the model group were given the 3% dextran sulfate sodium solution by the way of drinking for 7 d to build the rat model of inflammatory bowel disease, while rats in the control group were given free drinking of water. Six rats were executed at day 7, 14 and 21 respectively. The colonic tissues were collected from rats to observe the pathological changes of colonic mucosa. The activity of myeloperoxidase was detected and the white blood count was performed for rats in each group. The Ussing chamber technique was employed to detect the transepithelial electrical resistance (TER) and short-circuit current (SC) of colonic mucosa of rats in different time intervals; the quantum dots labeling technique was employed to detect the expression level of claudin-1 and claudin-2 in the colonic tissues.@*RESULTS@#After the successful modeling, the weight of rats in the model group was significantly reduced, while the disease activity index score was increased. The weight was at the lowest level at day 14 and then it began to increase afterwards. The disease activity index score was at the highest level at day 12 and then it began to decrease gradually. The activity of myeloperoxidase and WBC for rats in the model group all reached the peak value at day 14 and then decreased gradually. There was no significant difference in the changes of TER and SC in different time intervals for rats in the control group (P > 0.05). TER of model group was at the lowest level at day 14 and then increased gradually; SC was at the highest level at day 14 and then decreased gradually. TER of model group at day 7, 14 and 21 was significantly lower than that of control group, while SC of model group was significantly higher than that of control group (P 0.05). The claudin-1 and claudin-2 for rats in the model group reached the highest level at day 14 and then decreased gradually. The claudin-1 and claudin-2 of model group at day 7, 14 and 21 was significantly higher than that of control group (P < 0.05).@*CONCLUSIONS@#After the acute stage, the inflammatory bowel disease is then in the chronic recovery stage; the increased permeability of colonic mucosa and increased expression of tight junction protein of intestinal epithelium are closely related to the pathogenesis and development of disease. The tight junction protein plays a key role in the pathogenesis of injured colonic barrier of inflammatory bowel disease.
ABSTRACT
Objective: To discuss the changes in the tight junction protein of intestinal epithelium and permeability of colonic mucosa and its possible mechanism by building the rat mode of inflammatory bowel disease at the chronic recovery stage. Methods: A total of 36 SD rats were divided into the model group and control one according to the random number table, with 18 rats in each group. Rats in the model group were given the 3% dextran sulfate sodium solution by the way of drinking for 7 d to build the rat model of inflammatory bowel disease, while rats in the control group were given free drinking of water. Six rats were executed at day 7, 14 and 21 respectively. The colonic tissues were collected from rats to observe the pathological changes of colonic mucosa. The activity of myeloperoxidase was detected and the white blood count was performed for rats in each group. The Ussing chamber technique was employed to detect the transepithelial electrical resistance (TER) and short-circuit current (SC) of colonic mucosa of rats in different time intervals; the quantum dots labeling technique was employed to detect the expression level of claudin-1 and claudin-2 in the colonic tissues. Results: After the successful modeling, the weight of rats in the model group was significantly reduced, while the disease activity index score was increased. The weight was at the lowest level at day 14 and then it began to increase afterwards. The disease activity index score was at the highest level at day 12 and then it began to decrease gradually. The activity of myeloperoxidase and WBC for rats in the model group all reached the peak value at day 14 and then decreased gradually. There was no significant difference in the changes of TER and SC in different time intervals for rats in the control group (P > 0.05). TER of model group was at the lowest level at day 14 and then increased gradually; SC was at the highest level at day 14 and then decreased gradually. TER of model group at day 7, 14 and 21 was significantly lower than that of control group, while SC of model group was significantly higher than that of control group (P 0.05). The claudin-1 and claudin-2 for rats in the model group reached the highest level at day 14 and then decreased gradually. The claudin-1 and claudin-2 of model group at day 7, 14 and 21 was significantly higher than that of control group (P < 0.05). Conclusions: After the acute stage, the inflammatory bowel disease is then in the chronic recovery stage; the increased permeability of colonic mucosa and increased expression of tight junction protein of intestinal epithelium are closely related to the pathogenesis and development of disease. The tight junction protein plays a key role in the pathogenesis of injured colonic barrier of inflammatory bowel disease.
ABSTRACT
Objective To investigate the protective mechanism of octahedral montone in rats with acute pancreatitis.Methods Seventy-two SD rats were randomly divided into a sham-operation ( SO) group, a severe acute pancreatitis (SAP) group and a treatment with octahedral montone group.Retrograde pancreatic ductal injection of 5% cholate sodium in rats was used to establish SAP models.Sham operation was done with intraperitoneal injection of normal saline.In the treated group octahedral montone was given through enema half hour before inducing SAP model.Then, we evaluate the pancreatic injury and detect the level of TNF-alpha, diamine oxidase ( DAO) and endotoxin.Western blot and RT-PCR were used to determine the expressions of the tight junction protein occludin in the endothelial cells of intestinal mucosa at the time of hour 3,6, 12 after operation.Results ( 1 ) The pathological scores of pancreatitis were significantly higher in the SAP group than those in the treatment group and SO group (P < 0.05 ).(2) Compared with the SO group, the level of TNF-alpha in the SAP group and the treatment group was much higher ( P < 0.05 ) , but the level in the treatment group was lower than that in the SAP group ( P < 0.05 ).(3) The serum concentration of DAO and endotoxin was significantly increased in the SAP group, and the concentration in treatment group was higher than that in the SO group (P <0.01) , but lower than that in the SAP group ( P <0.01 ).The occludin protein and mRNA expression in the SAP group was the lowest and the expression in the treatment group was higher than that in the SAP group (P <0.01) ,but lower than that in the SO group (P < 0.01).Conclusions Octahedral montone can improve the colonic barrier function, reduce the endotoxemia, and ameliorate the inflammation during acute pancreatitis.