Romagnano M A, Newton B W, Pierre A H, Hamill R W
Neurology Unit, Monroe Community Hospital, Rochester, NY 14603-0905.
Brain Res Dev Brain Res. 1989 Apr 1;46(2):263-79. doi: 10.1016/0165-3806(89)90290-3.
The postnatal distribution of enkephalin (Enk) fibers is described in preganglionic containing sympathetic nuclei in the rat thoracolumbar spinal cord. In high thoracic spinal cord, at birth, Enk fibers are present in moderate numbers in the intermediolateralis nucleus, pars principalis (ILp), and nucleus intercalatus spinalis (IC). Enkephalin fibers first appear in the dorsal commissural nucleus (dcn) on postnatal day 2. Postnatal day 6 represents a pivotal timepoint when the basic Enk innervation pattern is established. From postnatal day 11 through day 20 there is a gradual accumulation of Enk fibers within each of the sympathetic nuclei such that the density and distribution of immunoreactive fibers approaches the adult appearance by postnatal day 20. An adult pattern is achieved by postnatal day 30. There is a rostral-caudal gradient in the developmental appearance of Enk fibers in sympathetic nuclei such that the ILp nucleus contains Enk fibers on postnatal day 0 in the high thoracic spinal levels compared to postnatal day 6 in low thoracic-high lumbar spinal levels. Examination of the location of Enk fibers during ontogeny highlighted several additional features of the distribution of Enk fibers in the adult animal. Enkephalin fibers delineate two subdivisions of the IC nucleus; a thin dense core of Enk fibers contained within a broader band of moderate numbers of Enk fibers. We also report variations in the general overall pattern of the Enk fiber distribution in high thoracic, middle thoracic, and lwo thoracic-high lumbar spinal cord levels.
本文描述了大鼠胸腰段脊髓中含交感神经节前神经元核团内脑啡肽（Enk）纤维的产后分布情况。在出生时，高胸段脊髓的中间外侧核主部（ILp）和脊髓中间插入核（IC）中有中等数量的Enk纤维。脑啡肽纤维在出生后第2天首次出现在背连合核（dcn）。出生后第6天是一个关键时间点，此时基本的Enk神经支配模式得以确立。从出生后第11天到第20天，每个交感神经核团内的Enk纤维逐渐积累，使得免疫反应性纤维的密度和分布在出生后第20天接近成年状态。到出生后第30天形成成年模式。交感神经核团中Enk纤维的发育出现存在头-尾梯度，例如在高胸段脊髓水平，ILp核在出生后第0天就含有Enk纤维，而在低胸段-高腰段脊髓水平则在出生后第6天才含有。对个体发育过程中Enk纤维位置的检查突出了成年动物中Enk纤维分布的几个其他特征。脑啡肽纤维勾勒出IC核的两个亚区；在数量适中的较宽Enk纤维带内包含一条细而密集的Enk纤维核心带。我们还报告了高胸段、中胸段和低胸段-高腰段脊髓水平Enk纤维分布总体模式的变化。
