成年大鼠去皮层血管引起前脑室下区祖细胞增殖迁移并形成迁移路至损伤部位(一)祖细胞增殖迁移的部位在背外侧脑室下区

成年哺乳动物脑室下区(SVZ)富有神经干细胞、神经细胞祖细胞和胶质细胞祖细胞,它们能生成新的神经细胞、星状胶质细胞和少突胶质细胞。SVZ中的神经细胞祖细胞能形成切线形式的嘴侧迁移流(RMS)到嗅球,在嗅球分化成成熟的中间神经元。近年来证明成年动物实验性脑损伤和变性疾病都能引起SVZ细胞增生并能向非嗅球区迁移。本研究将成年大鼠一侧大脑皮层血管去除,15d和30d后取前脑作冠状及矢状连续切片,用BrdU和PCNA抗体显示前脑室下区正在分裂的细胞;用Tuj1抗体显示神经元祖细胞;用GFAP和vimentin抗体显示胶质细胞祖细胞。结果证明去除一侧皮层血管引起术侧及其对侧的背外侧脑室下区(dl-SVZ)的上述免疫反应阳性细胞明显增多,并向胼胝体迁移,在胼胝体内形成放射形式迁移路至损伤部位。本研究表明背外侧脑室下区的范围应包括背外侧角、外侧伸展和侧脑室上壁的SVZ,它们是切线形式和放射形式两种不同方向的迁移路祖细胞的共同源地。

THE PROGENITOR CELLS IN THE ANTERIOR SUBVENTRICULAR ZONE INCREASE PROLIFERATION AND MIGRATION THAT FORM MIGRATORY PATHWAY TO THE SITE OF LESION IN THE ADULT RAT AFTER CORTICAL DEVASCULARIZATION (1) THE DORSOLATERAL SUBVENTRICULAR ZONE AS A SOURCE OF THE PROLIFERATING AND MIGRATING PROGENITORS

The subventricular zone(SVZ) of the adult mammalian forebrain contains stem cells, neuronal progenitors and glial progenitors which give rise to neurons, astrocytes and oligodendrocytes. The neuronal progenitors in the SVZ migrate tangentially along the rostral migratory stream into the olfactory bulb where they differentiate into local interneurons. Accumulating evidence indicated that injury or neurodegeneration induced cell proliferation and migration of the SVZ. In this study cortical devascularization was performed on the one side of cerebral hemisphere of the adult rat. The anterior SVZ(aSVZ) were examined by using the cell cycle marker BrdU and PCNA , the immature neuronal maker Tuj1 and the glial markers GFAP and vimentin. We observed a significant increased proliferation of the neuronal and glial progenitors in the ipisilateral and contralateral dorsolateral SVZ (dl-SVZ) which includs the SVZ of dorsolateral corner, lateral extension and upper wall of the lateral ventricle. The proliferating progenitors migrated out from the dl-SVZ into the courpus callosum aggregated to form radial migratory pathway. Our results indicate that the dl-SVZ is the source of the progenitors of both radial and tangential migratory pathways in the adult rat.