糖尿病大鼠心肌NF-κB、iNOS、COX-2表达的研究

目的：观察核因子-κＢ（ＮＦ-κＢ）、诱导型一氧化氮合酶（iNOS）以及环氧化酶-2（COX-2）3种炎症因子在糖尿病大鼠心肌组织的表达。方法:30只SD大鼠随机分为正常对照组和糖尿病组，糖尿病组大鼠按60 mg/kg的剂量1次性腹腔注射链脲菌素。实验于24周末结束，观察2组大鼠的体重、平均血糖浓度、心重指数。并取心肌组织石蜡切片分别行NF-κＢ、iNOS和COX-2免疫组化染色。同时用凝胶电泳迁移率（EMSA）的方法测定心肌组织ＮＦ-κＢ活性。结果:(1)糖尿病大鼠心肌组织ＮＦ-κＢ阳性表达细胞明显多于对照组；（2）EMSA方法显示，糖尿病大鼠心肌组织ＮＦ-κＢ表达强度明显高于对照组；（3）对照组大鼠心肌组织未见iNOS的表达，糖尿病大鼠见明显iNOS的表达；（4）对照组大鼠心肌组织偶见COX-2的表达，糖尿病大鼠见明显COX-2的表达。结论:NF-κＢ、iNOS和COX-2在糖尿病大鼠心肌组织中表达活性明显增强。

Expression of myocardial NF- κB, iNOS and COX-2 in diabetic rats

AIM: To investigate the expression of nuclear factor-κB (NF-κB), inducable nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in diabetic myocardium. METHODS: Thirty SD rats were randomly divided into control and experimental groups. Diabetes was induced by a single intraperitoneal injection of STZ. The weight, blood glucose level and heart weight index (HWI) were measured 24 weeks after injection. The myocardial NF-κB, iNOS and COX-2 were stained at the same time. Furthermore, NF-κB activation in myocardium was investigated by electrophoretic mobility shift assay (EMSA).RESULTS: (1) Compared to the normal rats, the NF-κB-positive cells in the myocardium in diabetic rats significantly increased. (2) NF-κB activation in myocardium by EMSA was significantly higher in the diabetic rats than that in the normal rats. (3) The iNOS was not expressed in normal rat myocardium and was significantly expressed in the diabetic rat myocardium. (4) The COX-2 was rarely expressed in normal rat myocardium and was significantly expressed in the diabetic rat myocardium.CONCLUSION: The expressions of NF-κB, iNOS and COX-2 are significantly enhanced in the diabetic myocardium.