云母对NSAIDs相关性小肠黏膜损伤COX-2及HSP70表达的影响

目的：研究NSAIDs相关性小肠黏膜损伤COX-2及HSP70表达，探讨云母对小肠黏膜的保护机制。方法：24只SD大鼠，随机分为对照组、模型组、云母组，每组8只。模型组和云母组每天予双氯酚酸钠溶液7.8mg/（kg·d）剂量灌胃，制备大鼠NSAIDs相关性小肠黏膜损伤模型，云母组每天造模前予云母液120mg/（kg·d）剂量灌胃。灌胃给药5天后处死大鼠，进行大体形态观察，肠黏膜损伤指数（CMDI）及病理Chiu氏评分；免疫组化法检测小肠黏膜COX-2及HSP70表达。结果：与对照组比较，模型组CMDI、Chiu氏评分及COX-2、HSP70表达水平明显升高（P＜0.01）。而云母组CMDI、Chiu氏评分及COX-2表达水平较模型组有明显下降（P＜0.01），HSP70水平更进一步升高（P＜0.01）。结论：NSAIDs相关性小肠黏膜损伤与COX-2及HSP70表达有关，云母可抑制损伤小肠黏膜COX-2表达，同时增强HSP70表达，从而对小肠黏膜起到保护作用。

Effects of Mica on COX-2 and HSP70 of NSAIDs -induced small intestinal damage

Objective：To study the effect of mica on the expression of COX-2 and HSP70 in non-steroidal anti-in-flammatory drugs （NSAIDs）-induced small intestinal damage and to approach the protective mechanism of mica. Methods：Twenty-four rats were randomly divided into control group,model group,and mica group,8 rats in each group. With the exception of rats in control group,all rats were intragastrically administered with diclofenac sodium （7.8 mg/kg） for 5 days to establish the model of NSAIDs-induced small intestinal damage. The rat in mica group were given daily intragastric administration of mica （120mg/kg）before administration of diclofenac sodium. All rats were killed on day 5. At that time, the colonic mucosal damage index （CMDI） and Chiu score were evaluated and the expression of COX-2 and HSP70 were measured by biochemical and immunohistochemical methods. Results：Compared with control group,the rat in model group had significantly increased CMDI,Chiu score,and COX-2 and HSP70 （P〈0.01）. Mica treatment resulted in significantly decreased CMDI,Chiu,and COX-2,but more activities of HSP70 in comparison with model group （P〈0.01）. Conclusion：NSAIDs-induced small intestinal damage was related to the expression of COX-2 and HSP70,and mica may offer protective effects against the damage by decreasing the expression of COX-2 and increasing the expression of HSP70.