末端回肠炎大鼠模型Toll样受体2、4及髓样分化因子88的变化及其意义

Changes and Significance of TLR2,TLR4 and MyD88 in the Process of Experimental Terminal Ileitis of Rat Model

目的:探讨Toll样受体2(TLR2)、Toll样受体4(TLR4)、髓样分化因子88(MyD88)在实验性慢性末端回肠炎(CTI)发病过程中表达水平的变化及其相关意义。方法:60只雄性清洁级SD大鼠随机分成造模组、缝线组、对照组。分别利用肉眼及镜下观察、Western Blot方法,分析3种因子在CTI发病中的变化及其相关性。结果:(1)术后2周及8周,肉眼及镜下观见造模组表现分别为急性及慢性炎症反应。(2)术后8周与2周对比,结果表明TLR2、TLR4、MyD88在末端回肠炎的发病过程中有明显的升高。TLR4表达水平的升高率更显著。(3)在实验性末端回肠炎发病过程中TLR2、TLR4、MyD88表达呈正相关。结论:(1)TLR2、TLR4、MyD88在CTI中表达增加,均与组织炎症程度呈正相关;(2)TLR4表达水平在CTI发病时较TLR2及MyD88升高更显著,推测革兰阴性菌感染可能是CTI发病的启动因子。

Objective To investigate the changes and significance of TLR2, TLR4 and MyD88 in the process of experimental terminal ileitis. Methods 60 male SD rats were divided into three groups （model group, suture group and control group） randomly and equally. We observed the tissues with naked eyes first and then imbedded them with paraffin to observe the pathological sections under microscope. The changes and expressions of TLR2, TLR4, MyD88 and its mRNA were examined by Western Blot and RT -- PCR. At last the changes of the three molecules and their correlation were analyzed. Results I. In the 2nd postoperative week, tissues of model group showed acute inflammation under both microscope and naked-eye observation. In the 8th postoperative week, chronic inflammation occurred in model group. 2. Compared with 2 weeks after operation, the results showed that TLR2, TLR4 and MyD88 were significantly increased in the pathogenesis of terminal ileitis. TLR4 expression level of the rate of increase is more significant. 3. There was a positive correlation between TLR2, TLR4 and MyD88 expression in the pathogenesis of experimental terminal ileitis. Conclusions 1. In the progress of CTI, TLR2, TLR4 and MyD88＇s expression showed increasing expression and was positively related to the degree of inflammation. 2. Rise of expression levels of TLR4 could be more obvious than that of both TLR2 and MyD88, the gram negative bacilli may be the initiator of CTI.