皮质发育障碍模型鼠脑皮质、海马光镜体视学研究  

Light microscope stereological study of cortical dysplasias in cerebral cortex and hippocampus of rat model

作　　者：马勋泰[1] 唐勇[2] 吕洋[3] 承欧梅[3] 晏勇[3] 

机构地区：[1]泸州医学院附属医院神经内科,泸州646000 [2]重庆医科大学基础医学院组织学与胚胎学教研室,干细胞与组织工程实验室 [3]重庆医科大学附属第一医院神经内科,重庆400016

出　　处：《重庆医科大学学报》2012年第1期1-5,共5页Journal of Chongqing Medical University

基　　金：国家自然科学基金资助项目(编号:30570636);四川省教育厅重点资助项目(编号:09ZA046);四川省卫生厅资助项目(编号:090231);泸州市科技局资助项目[编号:泸市科计(2009)1号];泸州医学院青年基金资助项目(编号:09013);泸州医学院附属医院人才基金资助项目(编号:09057)

摘　　要：目的:主要探寻弥漫性皮质发育障碍(Diffuse cortical dysplasias,DCD)大鼠大脑半球、海马的体积变化和皮质下异位结节中神经元的形态、数量,探讨DCD所致难治性癫痫(Intractable epilepsy,IE)的发生机制。方法:建立X射线照射诱导的皮质下异位结节大鼠DCD模型,使用组织病理学和体视学技术观察DCD鼠大脑半球、海马的体积变化和皮质下异位结节中神经元的形态、数量等。结果:从出生到成年后DCD大鼠体重平均减少19%(P>0.05)。出生时DCD鼠脑质重较正常,从7 d～31周时仅平均为正常对照组的57%(P<0.05)。出生时DCD鼠脑体积正常,P7以后各时期DCD鼠脑体积平均减少36%(P<0.05)。虽然DCD鼠脑皮质体积也平均减少19%,并随着年龄的增加体积减少越明显,但无显著差异(P>0.05)。DCD鼠从P7以后海马体积平均减少39%(P<0.05),且CA1区体积也随龄增加而平均减少32%,但仅P56和P84与同龄对照组比较明显减少38%和36%(P<0.05)。皮质/大脑半球、海马/大脑半球和CA1/海马的体积分数各年龄组平均减少20%、21%和27%,但仅P56和P84的CA1/海马明显减少37%和35%(P<0.05)。各龄DCD组皮质Ⅰ层、海马CA2区、CA3区、门区及齿状回区体积与对照组比较无统计学意义。DCD组皮质下白质中的异位结节与正常对照组或母鼠组皮质下白质中神经元数密度、细胞数密度、神经元百分比比较增加99、121倍和64倍,有显著统计学意义(P<0.05),神经元细胞核费莱特直径Feret’s diameter的平均水平比较无统计学意义。DCD鼠大脑、海马体积减小主要是冠状位的缩短。DCD大鼠皮质第Ⅰ层异位结节、皮质下异位结节和海马异位结节结构及细胞特征比较与皮质Ⅱ～Ⅲ层皮质结节相似。结论:DCD鼠皮质第Ⅰ层、皮质下白质和海马异位结节未迁移到皮质Ⅱ～Ⅲ层。生物体视学方法能检测大鼠大脑的精确病理学构成,是一种很好的研究方法。Objective：To observe the precise pathological characteristics（cerebral hemisphere and hippocampal volume,neuronal quantity and so on） of animal models of diffuse cortical dysplasias（DCD） in cortex with stereological methods,and to discuss the mechanism of pathologic changes and epileprogenesis in this model.Methods：An animal model of DCD was established by exposing pregnant SD rats to X ray using a single dose of 150 cGy on embryonic day 17（E17） for 84 seconds.Slice was followed by quantitative analysis of neuron density,cell,diameter of nucleus,the distribution（DCD） and white matter neurons using Gundersen two-dimensional cell counting methods.Statistics analysis was used with mean standard deviation（x±s）,P0.05 representing significant,and student test analysis.Results：From birth to adult rats,the weight of body and brain of DCD rats decreased about 19%（P0.05） and 57%（P0.05） respectively.The volume of brain,cortex,hippocampus and CA1 decreased about 36%（P0.05）,19%（P0.05）,39%（P0.05） and 32%（P0.05） respectively,but only P56 and P84,compared with the same age group,decreased 38% and 36%（P0.05） respectively.Cortex/brain,hippocampus/brain,and CA1/hippocampus decreased about 20%,21%and 27% respectively in DCD rats,but only P56 and P84 for CA1/hippocampus was significantly reduced by 37% and 35%（P0.05）.HE stain and Nissl stain showed there were clusters of large neurons in both superficial and deep layers in the model rats＇ cortex.Neuron density,cell density and neuron percentage increased 99 times,121 times,and 64 times respectively in DCD rats with statistical significance（P0.05）.The average level of neuronal nuclei Feret＇s diameter was not statistically significant.DCD rat brain,and hippocampal volume reduction lay mainly in coronal shortening.In DCD rat,ectopic nodules,subcortical heterotopic nodules and ectopic hippocampal structure and cell characteristics of nodules of cortical layer Ⅰ were similar compared with the cortical nodules of Ⅱ~Ⅲ

关 键 词：皮质发育障碍 大脑皮质 海马 体视学 癫痫 

分 类 号：R742.8[医药卫生—神经病学与精神病学]