INVESTTGATON OF FACTORS PROMOTING HIPPOCAMPAL SCLEROSIS IN THE MOUSE MODEL OF PROGRESSIVE HYPERTROPHY OF DENTATE GYRUS IN HIPPOCAMPUS.

小鼠海马内一次性注射少量海人酸（KA），可引起海马颗粒细胞进行性弥散和增大，从注射KA后4d开始，持续到8周。本研究旨在探讨KA注射后海马神经元分化的影响因素。1、培养实验结果：KA注射后第7天，收集分散海马的蛋白质提取物和细胞外液（ECF）。将这两种样品加入神经干细胞或海马脑片的培养液中。将KA注射海马的蛋白提取物加入到海马片培养物中，诱导阿蒙角锥体细胞的神经元细胞变性。神经干细胞向神经元或神经胶质细胞的分化不受KA注射海马的蛋白提取物或ECF的影响。由于ECF与人工耳蜗无明显差异， ...更多信息 脑脊液是收集ECF的载体，ECF的浓度被认为是非常低的。从本质上讲，ECF比全细胞蛋白提取物更重要，以检查环境因素。然而，从小鼠海马中收集足够量的ECF用于本实验可能是相当困难的。如前所述（1），蛋白提取物对培养的海马锥体细胞有一定的神经毒性。这种神经毒性被认为与谷氨酸或其有关物质有关，因为已知动物会发生癫痫。它们的过度表达可能是颗粒细胞分散的原因。为了验证这一假设，给予谷氨酸拮抗剂，并检查齿状回的变化。结果表明，NMDA受体的激活调节了脑缺血再灌注损伤的发生。该结果已提交给Epilepsia.3：我们通过差异显示方法研究了分散海马中特异性表达的mRNA，这是以前科学研究资助金（C）的主题。Flamingo/Celsr 2被确定为可能与该分散相关的候选基因之一，该结果已在Brain Research上报道。少

Single injection of small amount of kainic acid (KA) into mouse hippocampus induces the progressive dispersion and the enlargement of hippocampal granule cells that starts from 4days and lasts till 8weeks after KA injection. In this study, we investigated whether the factors that affect neuronal differentiations are involved or not in the KA injected hippocampus.1, The results of culture studies: At 7 days after KA injection, protein extracts and extracellular fluid (ECF) of the dispersed hippocampus were collected. These two kinds of samples were added to the culture medium of neuronal stem cells or hippocampal slices. Adding the protein extract from the KA injected hippocampus onto slice hippocampal culture induced the neuronal cell degeneration of pyramidal cells of Ammon's horn. The neuronal stem cells did not influenced their differentiation to neuron or glia either by protein extracts or ECF of KA injected hippocampus. Since the ECF did not induce any difference from the artifici … More al cerebrospinal fluid, which is a vehicle to collect the ECF, the concentration of ECF was thought to be very low. Essentially ECF is more important than whole cell protein extracts to examine the environmental factors. However it might be quite difficult to collect enough amount of ECF for this experiment from mouse hippocampus. Another animals or method will be needed for future studies.2: As mentioned above (1), protein extract showed some neurotoxicity to pyramidal cells of slice cultured hippocampus. This neurotoxicity was supposed to relate to glutamate or their related substances since the animals have been known to develop epilepsy. And their over-expression might be a cause of granule cell dispersion. To examine this hypothesis the antagonists of glutamate were administrated and the changes of dentate gyros were examined. And we found that the activation of NMDA receptor regulates the development of the dispersion. This result was submitted to Epilepsia.3: We investigated the mRNA, which were expressed specifically in dispersed hippocampus, by differential display method as an theme of the previous Grant-in-Aid for Scientific Research ( C ). Flamingo/Celsr2 was identified as one of the candidate gene that might be related to the dispersion, and the result was reported in Brain Research. Less