Barber R P, Phelps P E, Vaughn J E
Division of Neurosciences, Beckman Research Institute of the City of Hope, Duarte, California 91010.
J Comp Neurol. 1991 Sep 22;311(4):509-19. doi: 10.1002/cne.903110406.
The time at which a neuron is "born" appears to have significant consequences for the cell's subsequent differentiation. As part of a continuing investigation of cholinergic neuronal development, we have combined ChAT immunocytochemistry and [3H]thymidine autoradiography to determine the generation patterns of somatic and autonomic motor neurons at upper thoracic (T1-3), upper lumbar (L1-3), and lumbosacral (L6-S1) levels of the rat spinal cord. Additionally, the generation patterns of two subsets of cholinergic interneurons (partition cells and central canal cluster cells) were compared with those of somatic and autonomic motor neurons. Embryonic day 11 (E11) was the first day of cholinergic neuronal generation at each of the three spinal levels studied, and it also was the peak generation day for somatic and autonomic neurons in the upper thoracic spinal cord. The peak generation of homologous neurons at upper lumbar and lumbosacral spinal levels occurred at E12 and E13, respectively. Somatic and autonomic motor neurons were generated synchronously, and their production at each rostrocaudal level was virtually completed within a 2-day period. Cholinergic interneurons were generated 1 or 2 days later than motor neurons at the same rostrocaudal level. In summary, the birthdays of all spinal cholinergic neurons studied followed the general rostrocaudal spatiotemporal gradient of spinal neurogenesis. In addition, the generation of cholinergic interneurons also followed the general ventrodorsal gradient. In contrast, however, autonomic motor neurons disobeyed the rule of a ventral-to-dorsal progression of spinal neuronal generation, thus adding another example in which autonomic motor neurons display unusual developmental patterns.
神经元“诞生”的时间似乎对细胞随后的分化有着重大影响。作为对胆碱能神经元发育持续研究的一部分，我们结合了胆碱乙酰转移酶免疫细胞化学和[3H]胸腺嘧啶核苷放射自显影技术，以确定大鼠脊髓上胸段（T1 - 3）、上腰段（L1 - 3）和腰骶段（L6 - S1）躯体和自主运动神经元的生成模式。此外，还将胆碱能中间神经元的两个亚群（分隔细胞和中央管簇细胞）的生成模式与躯体和自主运动神经元的生成模式进行了比较。胚胎第11天（E11）是所研究的三个脊髓节段中每个节段胆碱能神经元生成的第一天，也是上胸段脊髓中躯体和自主神经元生成的高峰期。上腰段和腰骶段脊髓水平同源神经元的生成高峰期分别出现在E12和E13。躯体和自主运动神经元同步生成，并且它们在每个头尾水平的生成在2天内基本完成。胆碱能中间神经元比同一头尾水平的运动神经元晚1或2天生成。总之，所研究的所有脊髓胆碱能神经元的生成时间遵循脊髓神经发生的一般头尾时空梯度。此外，胆碱能中间神经元的生成也遵循一般的腹背梯度。然而，与之相反的是，自主运动神经元违背了脊髓神经元生成从腹侧到背侧的进展规律，从而又增加了一个自主运动神经元表现出异常发育模式的例子。
