成年白腰文鸟端脑新生神经元的光镜和电镜研究

应用光镜和电镜放射自显影方法,对成年雄性鸣禽白腰文鸟脑中新生神经元的起源和分布进行研究,结果发现,（１）端脑室带区（ＶＺ）中存在不均匀分布的（＾３Ｈ）标记细胞,大量标记细胞分布在端脑尾侧新纹状体水平（Ｌ１－Ｌ１４）的ＶＺ,形成标记细胞的“热点”区１（２）标记细胞经两次有丝分裂后,大约在肌肉注射（＾３））的第６天后开始从ＶＺ向外迁移,在３０天左以达目的脑区分化成为成熟神经元,这些神经元不均匀分布在端

STUDY OF NEWBORN NEURONS IN TELENCEPHALON OF ADULT STRIATED MANNIKIN:LIGHT AND ELECTRON MICROSCOPY

With light and electron microscopic autoradiography, the origination and distribution of the newborn neurons in adult "critical-period" songbird, Striated Mannikin were studied. The results showed that: (1) Many proliferating cells were distributed unevenly in the ventricular zone(VZ) of telencephalon, and the 3H] labeled cells were found to be populated in the lateral ventricular zone of neostriatum at brain level L12~L14,forming proliferation "hot spots"; (2) Having underwent mitosis twice, the proliferative cells in the VZ began to migrate laterally 6 days after intramuscular injection of 3H] thymidine, and these migrating precursor cells terminated at their targets and differentiated into new neurons on the 30th day. The newborn neurons distributed throughout the telencephalon, mainly in the neostriatum caudale, and pars medialis (NCM); (3) Ultrastructural observation showed that newborn neurons in the NCM had the same morphologic characteristics as mature neurons and they formed synaptic connections with distant targets. These data suggest that newborn neurons in adult "critical-period" songbirds are originated only from the ventricular zone of telencephalon and distributed mainly in the NCM, and that they are functional neurons with typical features of mature neurons.