The Significance Of Goblet Cells And Their Mucin-2 In The Pathogenesis Of Experimental Terminal Colitis

Objective: To investigate the changes and significance of goblet cells and mucin-2 in the pathogenesis of experimental terminal colitis.Method: 60 male SD rats divided into three groups randomly: control group named D,only abdominal cavity anaesthesia;suture group named F,only abdominal cavity anaesthesia;model group named Z,ileocecal part was searched after laparotomy under aseptic condition,ileum terminal anastomosis and cecal side anastomosis were adopted,and abdominal closure was performed after operation.All the animals in the group D,group F group Z were killed under deep anesthesia at the 2nd week and 8nd week after operation.The mucous membrane of the distal ileum of SD rats(2 cm apart from the distal end of the anastomotic anastomosis and 4 cm long)was collected from the distal ileum of SD rats.The tissue specimens were fixed by polyformaldehyde and embedded in paraffin sections and stained by HE staining and mucin-2 immunohistochemistry staining respectively.The morphologic characteristics of goblet cells and the changes of mucin-2 in each group were observed.Results : 1.Each SD rat ileum mucosa tissue of the eye view results,2 weeks after operation,the ileal mucosa of F group and Z group with acute inflammation under eye view.Inflammation was more obvious in Z group.There were no special performance under eye view in D group,The difference of inflammation score of the ileal mucosa of Z and F group respectively compare to D group was statistically significant under eye view in SD rats(P<0.05).After 8 weeks,Z group under eye view: chronic inflammation reaction.No obvious inflammatory changes were found under the eye of ileal terminal mucosa in group F and D respectively.There was a significant difference between group Z compared to group F and D(P < 0.05).2.The microscopical findings of distal ileal mucosa in group F and Z after 2 weeks surgery were as follows: the lesions mainly involved the mucosal layer,mainly included acute inflammation,multiple inflammatory cell infiltration,mainly neutrophils and a small number of lymphocytes.8 weeks after operation,the inflammatory cells in the terminal ileum of SD rats in group Z were gradually aggravated,the lesion mucosa and submucosa were damaged,and the inflammatory cells were mainly lymphocytes and plasma cells,a small number of eosinophils.Proliferation,erosion,ulcers,bleeding,polyps or mucosal thinning,atrophy,mucosal glands decreased or disappeared,villus structure was unclear or disappeared.3.Under the microscope,2 weeks after surgery,goblet cell vacuolization,began to increase,mainly for acute inflammation,the emergence of a variety of inflammatory cell infiltration,cell gap swelling,cells began to appear the boundary line is not clear,location of the intestinal tract secretion hole began to increase intestinal microvilli but more dense villi was relatively flat.The structure is unclear or disappeared.After 8 weeks,goblet cells increased obviously,high density scattered between columnar cells,the boundary of each cell was unclear,the cell arrangement was disordered,the morphology was abnormal,the interstitial space infiltrated,the interstitial plasmacyte infiltrated,the mucosal myometrium edema.At the same time,intestinal secretion pore density increased,intestinal microvilli dense and different length.The histological features of distal ileum mucosa of SD rats in group F were as follows: inflammation was gradually alleviated and tissue injury was basically repaired at 8 weeks.4.Immunohistochemical and the correlation with inflammation analysis of ileal mucosa in SD rats.The mucin-2 was highly expressed in the distal ileal mucosa in Z group and F group 2 weeks after operation.There was a statistically significant difference compared to D group.The expression of mucin-2 in the distal ileal mucosa of Z group was increased 8 weeks after operation,and positively correlated with the degree of inflammation in the terminal ileum.The expression of mucin-2 in F group was not significantly increased compared to that in D group.Conclusions: 1.The goblet cells in the local tissues of experimental terminal colitis increased obviously,and the ultrastructure of the cells was abnormal.2.Goblet cell and mucin-2 were highly expressed in experimental terminal ileal enteritis and was positively correlated with the degree of inflammation in the terminal ileum.3.Goblet cell and their mucin-2 may play an important role in the pathogenesis of experimental terminal ileitis.