CX43在局灶性皮质发育不良模型的表达

Expression of Connexin 43 in focal cortical dysplasia model

目的建立局灶性皮质发育不良(focal cortical dysplasia,FCD)模型,并分析缝隙连接蛋白(connexin,CX) 43在FCD模型的表达。方法取孕鼠产后第1天Wistar乳鼠为实验对象,液氮冷冻Wistar乳鼠大脑皮质制作FCD模型。实验大鼠分为对照组10只与实验组60只(依据冷冻时间,再分为30 s组、60 s组和90 s组,各亚组20只)。实验动物造模满8周时,行脑组织苏木精-伊红染色及免疫组织化学染色,观察细胞形态与CX43表达。结果实验组48只大鼠FCD造模成功(30 s组18只、60 s组18只和90 s组12只)。对照组脑组织切片结构分界清晰,细胞形态正常。实验组脑组织切片可见层状结构和柱状结构紊乱,存在形态异常神经元和气球样细胞。CX43阳性细胞数:对照组19.90±3.221,30 s组45.24±3.185,60 s组46.15±3.299,90 s组46.66±3.230,各实验组阳性细胞数均较对照组明显增多,差异具有统计学意义(均P <0.05)。结论液氮冷冻方法可成功建立FCD Ⅲd动物模型。缝隙连接蛋白构成的非突触传递机制,在癫疒间放电扩散中扮演重要角色。FCD Ⅲd的异常病理改变导致CX43在FCD Ⅲd大鼠模型表达增强,CX43增多可明显促进癫疒间发生。

Objective To establish the focal cortical dysplasia(FCD)model and analyze the expression of connexin 43 in the FCD model.Methods The neonatal Wistar rats were selected as the experimental objects.The cerebral cortex of the neonatal Wistar rats was frozen with liquid nitrogen to establish the FCD model.The Wistar rats were divided into control group(n=10)and experimental group(n=60,according to the freezing time,subdivided into 30-s group,60-s group and 90-s group,20 per subgroup).The experimental animals were subjected to HE staining and immunohistochemical staining of brain tissues at 8 weeks,and the morphology of the cerebral cortex cells and the expression of CX43 were observed.Results In the experimental group,48 rats were successfully established as FCD model(18 rats in 30-s group,18 in 60-s group,and 12 in 90-s group).In the control group,the brain tissue sections of rats had clear structural boundaries and normal cell morphology.In the experimental group,the cerebral cortex showed disturbance of the lamellar structure and columnar structure,and there were morphologically abnormal neurons and balloon-like cells.CX43-positive cell number per field of vision was 19.90±3.221 in the control group,45.24±3.185 in the 30-s,46.15±3.299 in the60-s and 46.66±3.230 in the 90-s experimental groups.The number of positive cells in each experimental group was significantly higher than that in the control group(all P<0.05).Conclusions FCDⅢd animal model can be successfully established by liquid nitrogen freezing method.Nonsynaptic transmission mechanism composed of gap junction proteins plays an important role in the spread of epileptic discharges.Abnormal pathological changes of FCDⅢd lead to increased expression of CX43 in FCDⅢd rat models,and the increase of CX43 can obviously promote the occurrence of epilepsy.