磁共振弥散加权成像定量评估高血糖大鼠脑缺血再灌注早期神经元损伤的实验研究  

Experimental Study of Diffusion⁃weighted Imaging in Early Assessment of Neuronal Injury of Cerebral Ischemia/reperfusion in Hyperglycemic Rats

作　　者：李鹏 郑博文[1] 马艳梅 李艳 陈兵[2] 张建忠[1] 景丽 LI Peng;ZHENG Bowen;MA Yanmei;CHEN Bing;LI Yan;ZHANG Jianzhong;JING Li(Department of Pathology,School of Basic Medical Science,Ningxia Medical University,Yingchuan 750004,China;Radiology Department of the General Hospital,Ningxia Medical University)

机构地区：[1]宁夏医科大学基础医学院病理学系,银川750004 [2]宁夏医科大学总医院放射科,银川750004

出　　处：《中国医学计算机成像杂志》2023年第4期448-453,共6页Chinese Computed Medical Imaging

基　　金：国家自然科学基金(31960177);宁夏回族自治区重点研发项目(2020BEG03026)。

摘　　要：目的:探讨高血糖大鼠脑缺血再灌注(CI/R)早期磁共振弥散加权成像(DWI)表观弥散系数(ADC)值与神经元损伤的关系。方法:30只Sprague-Dawley大鼠随机分为正常血糖假手术组(Sham,n=6)、正常血糖CI/R组(NG,n=12)和高血糖CI/R组(HG,n=12)。大鼠脑缺血30 min再灌注24 h后行MRI检查,之后获得病理组织标本。采用T2WI测量脑梗死体积,DWI测量缺血皮质区和纹状体区相对ADC(rADC)值,苏木精-伊红(HE)染色观察缺血区组织病理改变,免疫组织化学(IHC)染色计数皮质半暗带区神经元核抗原(NeuN)阳性细胞数,蛋白质印迹(WB)定量检测NeuN的表达水平。Pearson相关分析用于确定ADC值与病理指标的相关性。结果:T2WI测量高血糖大鼠脑梗死体积百分比高于正常血糖大鼠(P<0.05)。与NG组相比,HG组缺血皮质区和纹状体区rADC值显著增高(均P<0.01),且HG组缺血纹状体区rADC值与Sham组rADC值比较,差异无统计学意义(P>0.05)。HE染色显示HG组皮质半暗带区核固缩神经元数量显著高于NG组(P<0.01),缺血纹状体区组织水肿与NG组相比更加明显。IHC显示HG组NeuN阳性细胞数显著少于NG组(P<0.01)。WB显示HG组NeuN的表达量显著低于NG组(P<0.01)。大鼠CI/R早期缺血皮质区rADC值与核固缩神经元呈正相关(r=0.831;P<0.01),与NeuN阳性细胞数呈负相关(r=-0.689;P<0.05)。结论:与正常血糖大鼠相比,高血糖大鼠CI/R早期ADC值的显著增加代表着神经元损伤和血管源性脑水肿的加重,反映了CI/R损伤的程度。Purpose:To investigate the correspondence between the apparent diffusion coefficient(ADC)of diffusion weighted imaging(DWI)and neuronal damage in the early stage of cerebral ischemia/reperfusion(CI/R)in hyperglycemic rats.Methods:Thirty Sprague-Dawley rats were randomly divided into a normoglycemic sham operated group(Sham,n=6),a normoglycemic CI/R group(NG,n=12),and a hyperglycemic CI/R group(HG,n=12).After 30 minutes of ischemia followed by 24 hours of reperfusion,MRI examinations and pathological specimens were obtained sequentially.T2WI was used to measure the volume of cerebral infarction,DWI was used to measure the relative ADC(rADC)value of ischemic cortex and striatum,hematoxylin-eosin(HE)staining was used to observe the histopathological changes of ischemic area,immunohistochemistry(IHC)staining was used to count the number of neuronal nuclei(NeuN)positive cells in the cortex penumbra,and Western blotting(WB)was used to detect the expression level of NeuN.Pearson correlation analysis was used to determine the correlation between rADC values and pathological indicators.Results:The percentage of cerebral infarction volume measured by T2WI in hyperglycemic rats was higher than that in normoglycemic rats(P<0.05).Compared with NG group,the rADC values of ischemic cortex and striatum in the HG group were significantly higher(all P<0.01),and there was no significant difference between the rADC values of ischemic striatum in the HG group and Sham group(P>0.05).HE staining showed that the number of pyknotic neurons in the cortex penumbra of HG group was significantly higher than that of NG group(P<0.01),and the tissue edema in ischemic striatum was more obvious.IHC showed that the number of NeuN positive cells in the HG group was significantly less than that in the NG group(P<0.01).WB showed that the expression of NeuN in the HG group was significantly lower than that in the NG group(P<0.01).In the early stage of CI/R,the rADC value was positively correlated with pyknotic neurons(r=0.831;P<0.01),and negatively co

关 键 词：弥散加权成像 脑缺血再灌注 高血糖 神经元 

分 类 号：R445.2[医药卫生—影像医学与核医学]