Department of Anatomy and Neurobiology, and Institute of Neurodegeneration and Neuroregeneration, College of Medicine, Hallym University, Chuncheon, 200-702, South Korea.
Cell Mol Neurobiol. 2010 Aug;30(6):929-38. doi: 10.1007/s10571-010-9522-z. Epub 2010 Apr 20.
Neurogenesis occurs during the embryonic stage and throughout life. Brain injuries such as ischemic insults enhance cell proliferation in some areas of the brain. We examined proliferation of newly generated cells in each layer of the gerbil main olfactory bulb (MOB) after 5 min of transient cerebral ischemia using bromodeoxyuridine (BrdU) immunohistochemistry. Ischemia-related neuronal death in the MOB was not detected using Fluoro-Jade B histofluorescence and TUNEL staining. Many BrdU-positive ((+)) cells were found in the rostral migratory stream in control and ischemic MOBs. Significant increase of BrdU(+) cells was observed in the granule cell layer (GCL) and glomerular layer (GL) from 15 days post-ischemia, and BrdU(+) cells were very much higher than those of the control group 30 days post-ischemia. At this time point after ischemia/reperfusion, a few BrdU(+) cells in the GL and GCL were co-localized with calretinin(+) cells, and many BrdU(+) cells expressed doublecortin, a marker of immature neurons. These results indicate that cell proliferation is increased in the GCL and GL without apparent neuronal loss from 15 days after transient cerebral ischemia in gerbils.
神经发生发生在胚胎期和整个生命过程中。脑损伤，如缺血性损伤，会增强大脑某些区域的细胞增殖。我们使用溴脱氧尿苷 (BrdU) 免疫组织化学法检查了短暂性脑缺血后 5 分钟沙土鼠主要嗅觉球（MOB）各层中新生成细胞的增殖情况。使用氟罗丹明 B 组织荧光和 TUNEL 染色未检测到 MOB 中的与缺血相关的神经元死亡。在对照和缺血 MOB 中，均在嗅球的近端迁移流中发现了许多 BrdU(+)（+）细胞。从缺血后 15 天开始，在颗粒细胞层（GCL）和肾小球层（GL）中观察到 BrdU(+) 细胞的显著增加，并且 30 天后缺血组的 BrdU(+) 细胞明显高于对照组。在缺血/再灌注后的这个时间点，GL 和 GCL 中的少数 BrdU(+) 细胞与 calretinin(+) 细胞共定位，并且许多 BrdU(+) 细胞表达双皮质素，这是未成熟神经元的标志物。这些结果表明，沙土鼠短暂性脑缺血后 15 天，GCL 和 GL 中的细胞增殖增加，而没有明显的神经元丢失。
