论文部分内容阅读
目的观察老年大鼠局灶性脑缺血后室管膜下区(SVZ)和颗粒下层(SGZ)神经干细胞的增殖与分化。方法取老年大鼠制作大脑中动脉梗塞模型。用5-溴脱氧尿核苷(BrdU)脉冲标记结合免疫组织化学单标记技术,观察正常组、假手术组、脑缺血后3、71、4、212、8 d组SVZ和SGZ区BrdU阳性细胞的变化;用BrdU累积标记结合免疫组织化学双标技术,观察脑缺血14 d后SVZ和SGZ区BrdU/NeuN和BrdU/GFAP双标阳性细胞的数量。结果在正常组、假手术组及各脑缺血组大鼠的双侧SVZ和SGZ均可观察到BrdU阳性细胞。与正常组和假手术组相比,脑缺血后SVZ和SGZ区BrdU阳性细胞明显增加。缺血组SVZ区BrdU阳性细胞在脑缺血后7 d时达到高峰,28 d时仍高于正常水平;SGZ区BrdU阳性细胞在脑缺血后14 d时达到高峰,28 d时仍高于正常水平。通过BrdU累积标记和免疫组织化学双标发现:脑缺血14 d后,老年大鼠SVZ区有部分细胞显示BrdU/NeuN(0.98%)或BrdU/GFAP(12.56%)双标阳性,而SGZ区未见双标细胞。结论局灶性脑缺血可激活老年大鼠室管膜下区和颗粒下层的神经干细胞明显增殖,并且室管膜下区有部分增殖细胞可分化为神经元或神经胶质。
Objective To observe the proliferation and differentiation of neural stem cells in subventricular zone (SVZ) and subgrowth (SGZ) after focal cerebral ischemia in aged rats. Methods The middle cerebral artery occlusion model was made in aged rats. BrdU labeling was used to detect BrdU positive cells in SVZ and SGZ of normal group, sham operation group, 3,71,4,212,8 d after cerebral ischemia The number of BrdU / NeuN and BrdU / GFAP double positive cells in SVZ and SGZ were observed after 14 days of cerebral ischemia with BrdU labeling and immunohistochemical double labeling. Results BrdU positive cells were observed in bilateral SVZ and SGZ in normal group, sham operation group and each cerebral ischemia group. BrdU positive cells in SVZ and SGZ were significantly increased after cerebral ischemia compared with normal group and sham operation group. BrdU positive cells in SVZ of ischemic group peaked at 7 days after cerebral ischemia and remained higher than normal at 28 days. BrdU positive cells in SGZ reached the peak at 14 days after cerebral ischemia and remained higher than that at 28 days normal level. BrdU labeling and immunohistochemical double labeling showed that some cells in the SVZ of aged rats showed double positive of BrdU / NeuN (0.98%) or BrdU / GFAP (12.56%) after 14 days of cerebral ischemia, while SGZ No double-labeled cells. Conclusion Focal cerebral ischemia can activate the proliferation of neural stem cells in the subependymal and subgranular layers of aged rats, and some proliferative cells in the subependymal zone can differentiate into neurons or glia.