THE TIME OF GENESIS, EMBRYONIC ORIGIN AND DIFFERENTIATION OF THE BRAIN-STEM MONOAMINE NEURONS IN THE RHESUS-MONKEY
THE TIME OF GENESIS, EMBRYONIC ORIGIN AND DIFFERENTIATION OF THE BRAIN-STEM MONOAMINE NEURONS IN THE RHESUS-MONKEY
复制标题
DOI：
10.1016/0165-3806(82)90095-5
复制
发表时间：
1982-01-01
期刊：
影响因子：
--
通讯作者：
RAKIC, P
中科院分区：
文献类型：
--
作者：
LEVITT, P;RAKIC, P
在出生后的恒河猴中制备放射自显影图，分析蓝斑（LC）、黑质（SN）和中缝核（RN）的神经发生，这些恒河猴在165天妊娠期的选定胚胎（E）天暴露于[3 H]胸苷脉冲。重标记的单胺（MA）神经元仅存在于暴露于E27-E36之间的同位素的猴子中，峰值在E30-E33附近。E30产生的大多数神经元最终位于LC的内侧部分，而外侧部分的大多数细胞产生于E32和E33，表明存在中外侧时空梯度。在E32左右，用于LC紧凑部分的神经元的增殖达到峰值，而蓝斑下细胞的产生在整个E30-E33期间更均匀地进行。SN神经元在E36-E43之间产生，在E38-E40周围具有峰值标记，并且没有可感知的时空梯度。腹侧被盖区的神经元也在E38-E43之间产生。RN的神经发生发生在E28-E43之间，只有中等的喙尾时空梯度。中缝背肌和中央上级肌的神经元在E28-E35之间进行最终的有丝分裂，在E30时达到高峰，而中缝大肌、脑桥、暗肌和苍白肌的细胞在E35-E43之间产生，在E38-E40之间达到高峰。一般来说，投射到不同靶点的MA神经元可以在每个核内同时产生，而不管任何时空梯度。对暴露于[3 H]TdR后不同短时间间隔处死的另一系列胎儿的检查显示，所有MA神经元均出现在脑室区，每个MA核在脑干的特定水平产生。有丝分裂后MA细胞沿着沿着特定的途径迁移到它们的最终位置，并以与它们的发生顺序相对应的模式定居。形态计量学分析表明，在到达其最终目的地后，所有MA神经元的胞体和核根据相同的克里思和顺序生长，而不管其突触目标的发育时间表。
Neurogenesis of the locus coeruleus (LC), substantia nigra (SN) and raphe nuclei (RN) was analyzed in autoradiograms prepared from postnatal rhesus monkeys that had been exposed to a pulse of [3H]thymidine on selected embryonic (E) days of the 165-day gestational period. Heavily labeled monoamine (MA) neurons were present only in monkeys exposed to the isotope between E27-E36 with the peak around E30-E33. The majority of neurons generated on E30 eventually become situated in the medial part of the LC, whereas most cells of the lateral portion are generated on E32 and E33, indicating the existence of a mediolateral spatiotemporal gradient. Proliferation of neurons destined for the compact portion of the LC peaks around E32, whereas production of subcoeruleus cells proceeds more evenly throughout the E30-E33 period. SN neurons are generated between E36-E43, with peak labeling around E38-E40, and no appreciable spatiotemporal gradients. Neurons of the ventral tegmental area are also generated between E38-E43. Neurogenesis of the RN occurs between E28-E43 with only a moderate rostrocaudal spatiotemporal gradient. Neurons of raphe dorsalis and centralis superior undergo final mitosis between E28-E35, with the peak on E30, whereas cells of raphe magnus, pontis, obscurus and pallidus are produced between E35-E43, with the peak between E38-E40. In general, MA neurons that project to different targets may be produced simultaneously within each nucleus irrespective of any spatiotemporal gradients. Examination of another series of fetuses sacrificed at various short intervals after exposure to [3H]TdR revealed that all MA neurons arise in the ventricular zone with each MA nucleus being generated at a specific level of the brain stem. Postmitotic MA cells migrate to their final location along specific pathways, and settle in patterns corresponding to the sequence of their genesis. Morphometric analysis indicated that after reaching their final destinations, the somas and nuclei of all MA neurons grow according to the same tempo and sequence irrespective of the developmental schedules of their synaptic targets.