胃黏膜上皮紧密连接与实验性胃癌前病变的关系

Correlation between Tight Junction and Experimental Gastric Precancerous Lesion in Rats

目的 :探讨胃黏膜上皮紧密连接与实验性胃癌前病变的关系。方法 :大鼠分别饮用浓度为 4 0μg mL及 6 0 μg mL的甲基硝基亚硝基胍 (MNNG) ,以造成不同程度的胃癌前病变。在造模第 9周及 31周时观察胃黏膜病变情况及胃黏膜上皮紧密连接的改变。结果 :随造模时间及浓度的增加 ,模型鼠胃黏膜深度损伤指数、萎缩、肠化及异增等均加重 ,胃黏膜上皮紧密连接减少、细胞间隙增宽 (P <0 0 5 )。紧密连接受损程度与胃癌前病变程度呈正相关 (P <0 0 5 )。结论 :胃黏膜上皮紧密连接的损伤是胃黏膜萎缩发生、进展至癌变的重要环节 ;缩小上皮细胞间隙 ,保护胃黏膜屏障对于逆转胃癌前病变 。

Objective To explore the relation between tight junction of gastric mucosa epithelial and experimental gastric precancerous lesion.Methods Different degrees of gastric precancerous lesion in rats were induced by adminstering 40 μg/mL or 60 μg/mL N methyl N′ nitro N nitrosoguanidine(MNNG)in drinking water.Nine weeks and 31 weeks after the experimental,the pathological changes of gastric mucosa and tight junction were observed and compared with normal rats.Results Accompaning with the extension of MNNG exposure time and the increase of MNNG concentration,the injury index of gastric mucosa and the extent of pathological changes including atrophy,intestinal metaplasia and gastric epithelial dysplasia,etc.,persistently increased;tight junctions of gastric mucosa epithelials decreased and gastric epithelials gaps increased.In model rats,which were all significantly worse than those in normal rats( P <0 05),the injury degrees of gastric mucosa epithelial was positively correlated with the degrees of gastric precancerous lesion( P <0 05).Conclusions It suggests that the tight junction of gastric mucosa barrier play a key role in pathogenesis of gastric precancerour lesion.It also indicates that the reduction of gaps between epithelials and the protection of gastric mucosa barrier might have great signifiicance in reversing gastric precancerour lesion and in treatment of gastric carcinoma. China J Cancer Prev Treat,2003,10(3):259-262