The time of origin of neurons in Ammon's horn and the associated retrohippocampal fields
The time of origin of neurons in Ammon's horn and the associated retrohippocampal fields
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阿蒙角和相关海马后区神经元的起源时间
DOI：
10.1007/bf00304660
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发表时间：
1978
期刊：
影响因子：
--
通讯作者：
L. Swanson
中科院分区：
文献类型：
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作者：
Alice R. Schlessinger;W. Cowan;L. Swanson
本文用~ 3 H-胸腺嘧啶核苷放射自显影技术测定了大鼠海马齿状回门区、阿蒙角上区和区、海马后区的下托、下托前区、下托旁区、内外嗅区和嗅周皮质神经元的起源时间。在每个区域中，细胞在约5天的有限时间内产生，大多数在24-48小时内形成。与新皮质一样，海马区的细胞相对于它们产生的室管膜区以一种独特的“由内而外”的顺序产生。此外，沿着地层的横轴或齿鼻轴有两个明显的梯度，沿着。因此，齿状回门区（包括CA 4区）的神经元往往比下区的锥体细胞产生得更早，而这些锥体细胞平均而言又比下区的锥体细胞产生得更早。在海马后区，从嗅周皮层到前下托的内侧延伸有一个相当的梯度，平均而言，外侧内嗅区的细胞比内侧内嗅皮层的细胞形成得早，而这些细胞又比帕拉托或前下托的细胞产生得早。没有证据表明海马结构的任何部分存在背腹（或隔颞梯度），就像在齿状回中发现的那样。细胞计数表明，在上级区（CA 1区）有超过320，000个锥体细胞，在下级区（CA 2区和CA 3区）有约150，000个锥体细胞。
The time of origin of the neurons in the hilus of the dentate gyrus, in theregio superiorandregio inferiorof Ammon's horn, and in the following retrohippocampal fields — the subiculum, presubiculum, parasubiculum, medial and lateral entorhinal areas and the perirhinal cortex, has been determined in the rat, by the technique of3H-thymidine autoradiography. In each field the cells are generated over a limited period of about five days, with the majority being formed in a 24–48 h period. As in the neocortex, the cells in the various hippocampal fields are generated in a distinct “inside-out” sequence with respect to the ependymal zone in which they arise. In addition there are two distinct gradients along the transverse, or dentato-rhinal axis, of the formation. Thus the neurons in the hilar region of the dentate gyrus (including field CA4) tend to arise earlier than the pyramidal cells in theregio inferior, and these in turn, are on average, generated earlier than those in theregio superioror in thesubiculum. In the retrohippocampal region there is a comparable gradient extending medially from the perirhinal cortex to the presubiculum, the cells in the lateral entorhinal area being formed, on average, earlier than those in the medial entorhinal cortex, and these, in turn, are generated earlier than those in the para- or presubiculum. There is no evidence for a dorso-ventral (or septotemporal gradient) in any part of the hippocampal formation like that found in the dentate gyrus. Cell counts indicate that there are over 320,000 pyramidal cells in theregio superior(field CA1) and about 150,000 in theregio inferior(fields CA2and CA3).