慢性脑低灌注致大鼠肠黏膜损伤及claudin-3表达变化的研究

Study on CCH-induced intestinal mucosa injury in rats and changes in expression of claudin-3

目的观察慢性脑低灌注(CCH)大鼠回肠黏膜形态学及紧密连接蛋白claudin-3表达变化,并探讨两者的相关性。方法将80只健康雄性SD大鼠随机分为假手术组(Sham组)和慢性脑低灌注组(CCH组),采用永久性双侧颈总动脉结扎法建立CCH大鼠模型,Sham组只分离双侧颈总动脉而不结扎。两组分别于造模成功后1、4、12及24 w取回肠末段组织制成石蜡切片,伊红-苏木素(HE)染色,观察肠黏膜组织形态学变化;免疫荧光标记claudin-3检测其表达量的变化;对肠黏膜损伤程度与claudin-3表达量进行相关性分析。结果 CCH组较同时间Sham组回肠黏膜损伤明显(P <0.01);CCH组4 w、12 w及24 w与1 w比较损伤显著加重(P <0.01)。CCH组上皮细胞间claudin-3明显缺失(P <0.01),1 w时最显著,4、12、24 w后逐渐回升,但均较同时间Sham组显著减少。肠黏膜损伤程度与claudin-3表达水平呈负相关(P <0.05)。结论 CCH可致大鼠回肠黏膜持续性损伤及claudin-3表达减少,引发相关肠功能异常。

Objective To observe the morphology of chronic cerebral hypoperfusion(CCH)-induced intestinal mucosa injury in rats and the changes in the expression of tight junction protein claudin-3 and explore the correlation between them.MeAodfi A total of 80 healthy male SD rats were randomly divided into a sham-operated group(Sham group)and a CCH group.CCH rat model was established by permanent bilateral common carotid artery ligation.The bilateral common carotid arteries in the Sham group were isolated without ligation.One,four,12 and 24 weeks after successful modeling,distal bowel tissues in the two groups were taken back,made into paraffin sections and dyed with eosin-hematoxylin(HE)to observe the changes in the morphology of intestinal mucosa;immunofluorescent labeling was carried out to detect the changes in the expression quantity of claudin-3;correlation analysis■was conducted on the degree of intestinal mucosa damage and the expression of claudin-3.如suits The intestinal mucosal injury in the CCH group was more obvious than that in the Sham group(P<0.01);the injury four,12 and 24"weeks after successful modeling significantly deteriorated in the CCH group(P<0.01).The epithelium claudin-3 in the CCH group w,as obviously missing(P<0.01);it was the most significant in the first week and gradually increased after the fourth,12th and 24th weeks,but it was still significantly less than that in the Sham group in the same period.The degree of intestinal mucosal injury was negatively correlated to the expression level of claudin-3(P<0.05).Conclusion CCH can cause persistent injury of ileal mucosa in rats and the reduction of the expression of claudin-3 and cause related bowel dysfunction.