【摘要】 目的:检测SD大鼠脑缺血后缺血脑组织和外周免疫淋巴细胞干扰素-γ(IFN-γ)mRNA的表达,探讨IFN-γ在脑缺血中的作用。方法:用线拴封闭大脑中动脉的方法制作脑缺血动物模型,采用原位杂交的方法检测缺血脑组织及外周淋巴组织中IFN-γmRNA动态的变化情况。采用免疫组织化学方法检测缺血脑组织中浸润的T淋巴细胞数量。结合免疫组化和寡核苷酸探针杂交方法,检测T细胞表达IFNγ-。结果:①缺血脑半球IFN-γmRNA含量较假手术组明显增高(P<0.001),且随着脑缺血时间延长其表达量增加;②IFN-γmRNA表达数量随损伤面积扩大而增加(R=0.978 0,P<0.001);③缺血组外周血单核细胞IFN-γmRNA水平较假手术组明显增高,12小时达高峰(P<0.001),而脾淋巴细胞、淋巴结细胞IFN-γmRNA水平也均比假手术组明显增高,且随着脑缺血时间延长表达量增加(P<0.05、P<0.01、P<0.001);④随着脑缺血时间的延长,脑内浸润的T细胞数量显著增加(P<0.05、P<0.01、P<0.001)。结论:IFN-γmRNA表达主要参与大脑损伤后期反应过程,可能加重脑缺血后期的炎症反应。更多还原

【Abstract】 Objective:To detect whether focal cerebral ischemic enhances IFN-γ mRNA expression and to demonstrate whether IFN-γ was involved in the injury process after middle cerebral artery occlusion(MCAO) in rats.Methods:The middle cerebral arteries(MCA) of all experimental rats were occluded by inserting nylon monofilament in the right external carotid artery.IFN-γ in ischemic brain hemispheres and peripheral immune cells were examined by situ hybridization(ISH) from the 1st hour to the 6th day after middle cerebral ischemic occlusion(MCAO).We employed immunohistochemistry assay to detect cells infiltrating in brain tissue.The IFN-γ of T cells were analyzed by means of in situ hybridization and immunohistochemistry.Results:①The expression of IFN-γ mRNA in ischemic brain hemisphere was significantly higher than that in shamming operation group as time went by after MCAO(P<0.001),and the level of IFN-γ mRNA in ischemic brain hemisphere increased following with the time of injury.②IFN-γ mRNA expression increased correspondingly with the size of brain injury as time went by after MCAO(R=0.978 0,P<0.001).③The expression of IFN-γ mRNA of peripheral blood mononuclear cells in ischemic group were significantly higher than that in shamming operation group,and peaked at 12 h(P<0.001);The positive cells of IFN-γ mRNA of spleen cells and lymph nodes cells were significantly increased after MCAO than that in shamming operation group as time went by(P<0.05,P<0.01,P<0.001).④The number of T cells in the ischemic brain was increased as time went compared with that in shamming operation group(P<0.05,P<0.01,P<0.001).Conclusion:The data suggested that IFN-γ was mainly involved in the process of ischemic brain injury,aggravating the inflammatory reaction of later stage.更多还原