节点文献

皮质发育畸形大鼠皮质神经元AIS的可塑性研究

Plasticity of Neuron Axon Initial Segment of Cortex in Rats with Malformation of Cortical Development

【作者】 孙丹妮

【导师】 肖波;

【作者基本信息】 中南大学 , 临床医学, 2013, 博士

【摘要】 目的研究皮质发育畸形(MCD)仔鼠与正常仔鼠的生长发育差异,动态监测层特异性标志物Map1b和AIS的标记物AnkG在MCD大鼠皮质中的表达变化,揭示MCD大鼠皮质AIS区的可塑性改变,为深入探讨AIS对MCD大鼠模型癫痫易感的意义提供实验室依据。方法在SD大鼠胚胎17天时,向孕鼠腹腔注射卡莫司汀(BCMU),建立皮质发育畸形仔鼠模型,对照组在相同时间注射10%葡萄糖溶液。选择出生当天(P0),出生后7天(P7),14天(P14),28天(P28)和56天(P56)作为观察时间点,分别在各时间点选取对照组和MCD组仔鼠进行体重,脑湿重,身长的测量。在各时间点每组随机选取6只仔鼠用于制备石蜡切片和冰冻切片,采用HE染色方法观察两组仔鼠皮质的形态改变,免疫组织化学染色方法观察Maplb在两组皮质内的表达差异,并验证MCD模型是否成功,应用免疫荧光染色方法观察AnkG在两组皮质内的表达变化。结果两组仔鼠的体重在PO期无显著差异(P>0.05),从P7后开始,之后的各时间点体重差异有统计学意义(P<0.05);两组仔鼠的脑湿重在PO和P7无显著差异(P>0.05),从P14开始,之后的各时间点差异有统计学意义(P<0.05);两组仔鼠身长在各时间点均无显著差异(P>0.05)。Map1b在对照组仔鼠颞叶皮质中主要表达在Ⅱ,Ⅲ,Ⅴ层,在各时间点的表达模式无明显变化,Map1b在MCD组仔鼠颞叶皮质中表达在Ⅱ,Ⅲ,Ⅳ层。在MCD组仔鼠皮质中,AnkG阳性细胞形态与对照组存在显著差异,AIS形态正常化时间晚于对照组,AnkG阳性区域所代表的AIS长度在PO时与对照组无显著差异(P>0.05),从P7开始,之后的各时间点的AIS长度均短于对照组(P<0.05)。结论Map1b在MCD组仔鼠皮质中的表达位置由正常的ⅡⅢⅤ层转移到Ⅱ ⅢⅣ层对应的位置,提示在MCD大鼠皮质中,Map1b所标记的阳性细胞发生迁移异常;MCD组仔鼠脑皮质AIS的长度在出生一周后有所缩短,形态表现为螺旋状或锯齿状弯曲,形态正常化的时间延迟,提示MCD大鼠模型皮质神经元AIS发生可塑性改变。

【Abstract】 Object To study the development differences between the malformation of cortical development (MCD) and normal Sprahue Dawley (SD) rats. To observe the expression changes of layer-specific markers Maplb in MCD rats’ cortex. To investigate the expression of AnkG in MCD rats cortical AIS area, reveals the morphological changes of AIS area in the MCD rats’cortex, and then explore the significance to epilepsy susceptibility of MCD animal model.Methods The experimental group rats were induced cortical malformation with BCMU by intraperitoneal injection at the17th day of pregnantce. The control group were injected with10%glucose solution at the same time. Select the day of birth (P0),7days after birth (P7),14days (P14),28days (P28) and56days (P56) as the observation time, then we selected two groups with the same numbers of pups at each observation time, taking the weight, the brain wet weight, and height measurement. We randomly selected six pups from each group at each observation time for the preparation of paraffin sections and frozen sections. Observation of morphological changes of the two groups’cortex by HE staining, immunohistochemical staining was used to observ MAP1B expression in the cortex, and verify the success of the MCD model, immunofluorescence staining method used to observe the AnkG expression differences in the two sets of cortex.Results There were no significant difference (P>0.05) in weight between two groups at P0, the difference was significant starting from P7(P<0.05); There were no significant difference (P>0.05) in brain wet weight between two groups at PO and P7(P>0.05), it was significant starting from the time of P14(P<0.05); There were no significant difference (P>0.05) in height at any observation time. MAP1B expressed in Ⅱ, Ⅲ, Ⅴ layer in the temporal cortex of control group, no significant expression changes happened at any observation time, MAP1B expressed in Ⅱ, Ⅲ, Ⅳ layer in MCD group. There were significant differences in morphology of AnkG+cell between two groups, the normalization of AIS morphology in MCD group was later than that in the control group. The length of the AnkG+cell in MCD group were shorter than that in the control group from the time of P7(P<0.05).Conclusions The weight development of MCD group lagged far behind that in the control group from the first week after birth; The brain wet weight development of MCD group lagged far behind that in the control group from the second week after birth; There was no significant difference in height between two groups; Maplb+cell expressed in Ⅱ Ⅲ Ⅴ layer in the nomal group; The expression pattern of Maplb changed from different area in the MCD group, it expressed in Ⅱ, Ⅲ, Ⅳ layer in the temporal cortex; There were significant differences in the morphology of AIS between two group, There were significant differences in the length of AIS between two group from the first week after birth:the length of AIS is shortened in the MCD cortex, the normalization of AIS morphology delayed.

  • 【网络出版投稿人】 中南大学
  • 【网络出版年期】2014年 02期
  • 【分类号】R742.8
  • 【下载频次】53
节点文献中: 

本文链接的文献网络图示:

本文的引文网络