高血糖状态下大鼠脑缺血再灌注后不同时限点细胞间黏附分子1及肿瘤坏死因子α表达的差异

Different expressions of intercellular adhesion molecule-1 and tumor necrosis factor-alpha under hyperglycemic state at different time limit in rats after cerebral ischemia reperfusion

目的:观察高血糖状态下大鼠脑缺血再灌注后炎症介导因子细胞间黏附分子1以及促炎性细胞因子肿瘤坏死因子α在不同时限点的表达及其差异。方法:实验于2003-07/2004-03在大连医科大学附属第二医院中心实验室完成。36只雄性SD大鼠随机分成3组:正常血糖组16只、高血糖组16只和假手术组4只,其中高血糖组和正常血糖组又分为再灌注2,4,6,24h4个亚组。建立大鼠大脑中动脉缺血再灌注模型,其中高血糖组在阻断大脑中动脉前30min腹腔注射500g/L葡萄糖溶液(3g/kg),各组大鼠于麻醉状态下取脑组织制备冠状切片,观察脑组织细胞间黏附分子1、肿瘤坏死因子α表达采用免疫组织化学方法。结果:36只大鼠均进入结果分析。①各组大鼠脑组织细胞间黏附分子-1的表达:正常血糖组缺血2h再灌注2h可见细胞间黏附分子1表达犤(18.13±2.16)个/视野犦,再灌注24h达高峰犤(59.50±2.25)个/视野犦。与正常血糖组相比,高血糖组细胞间黏附分子1表达高峰提前至再灌注6h犤(76.75±2.14)个/视野犦。在再灌注2,4,6h高血糖组明显高于正常血糖组,再灌注24h时低于正常血糖组(P<0.01)。②各组大鼠脑组织肿瘤坏死因子α的表达:正常血糖组和高血糖组均在缺血2h再灌注2h时可见肿瘤坏死因子α的表达犤(7.81±1.60)个/视野,(11.65±1.90)个/视野,P<0.01犦,于再灌注24h达高峰犤(26.25±1.81)个/视野,(35.00±2.28)个/视野,P<0.01犦。在同一再灌注时间点明显高于正常血糖组(P<0.01)。结论:高血糖状态下细胞间黏附分子1及肿瘤坏死因子α均呈高表达,但细胞间黏附分子1的表达与肿瘤坏死因子α的表达具有时间上的差异。

AIM： To observe the expression and their differences of imflammation mediated factor intercellular adhesion molecule-1 （ICAM-1） and promting imflammation cell factor tumor necrosis factor-α （TNF-α） under hyperglycemia state and their differences in rats after cerebral ischemia reperfusion. METHODS： The experiment was done from July 2003 to March 2004 in the Center Laboratory of Second Affiliated Hospital of Dalian Medical University. Thirty-six male SD rats were randomly divided into 3 groups： normal blood sugargroup （n=16）, hyperglycemia group （n=16） and shamoperation group （n=4）. Reperfusion for 2, 4, 6, 24 hours was performde in four subgroups respectivdy （n=4） in hyperglycemia group and normal blood sugar group. Cerebral ischemic-reperfusion models were made, and rats in hyperglycemia group were injected with 500 g/L cartose solutions （3 g/kg）in abdominal cavity 30 minutes before blocking the middle cerebral artery. Rats in each group were took brain tissue to make into coronal section under drugged state, and then investigate the expression of ICAM-1 and TNF-α through immunohistochemical technique. RESULTS： Totally 36 rats were involved in the analysis of results. ① The expression of ICAM-1 in rats of every group： ICAM-1 expression was seen in normal blood sugar group after 2 hour ischemia and 2 hour reperfusion [（18.13±2.16） per visual field],and it reached peak after at reperfusion 24 hours [（59.50±2.25） per visual field]. Compared with normal blood sugar group,the peak of ICAM-1 expression in hyperglycemic group went ahead of schedule areperfusion 6 hours （76.75±2.14）. It was significantly higher in hyperglycemic group than that in normal blood sugar group re-perfusion 2, 4, 6 hours, while lower reperfusion 24 hours （P 〈 0.01 ）. ② The expression of TNF-α in every group： It was appeared at ischemia 2 hours and at reperfusion 2 hours both in normal blood sugar group and in hyperglycemic group [（7.81±1.60）, （11.65±1.90）, （P〈 0.01）], and reached the peak at reperfusion 24 hours [（26.25±1.81）, （35.00±2.28） per visual field, （P 〈 0.01）]. It significantly higher at the same reperfusion time than that in normal blood sugar group （P 〈 0.01 ）. CONCLUSION： The expression of ICAM-1 and TNF-α under hyperglycemia state is high, but there is a difference in the time between the expression of ICAM-1 and the expression of TNF-α.