Snyder-Keller A M
Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201-0509.
J Neurosci. 1991 Mar;11(3):810-21. doi: 10.1523/JNEUROSCI.11-03-00810.1991.
Nigrostriatal dopamine (DA) projections terminate in distinct patches during the late prenatal and early postnatal period in the rat. During the first postnatal week, patches of DA fibers overlap with clusters of striatal neurons that share several identified characteristics. The early segregation of striatal cell types into either these patches or the surrounding matrix becomes a permanent organizational feature of the striatum. In order to determine whether the heterogeneous distribution of DA influences the formation of cellular patches, the developmental organization of chemically identifiable cell types was examined in normal rats and in rats DA depleted as infants (0 or 3 d) or in utero (embryonic days 17-18). During the first postnatal week, corresponding patches of DA afferents and substance P (SP)-immunoreactive neurons existed in the striatum of normal animals, and AChE-positive zones overlapped these patches in the lateral striatum. Injection of 6-hydroxydopamine into the lateral ventricles of fetal or infant rats produced a dramatic loss of striatal DA terminals. Neither the patchy distribution of SP-immunoreactive neurons nor the distinctive pattern of AChE staining present during the first 2 postnatal weeks was disrupted. During the third postnatal week, cells immunoreactive for leu-enkephalin or calbindin-D28k were confined to the matrix compartment, and this compartmentalization was also not noticeably changed by pre- or postnatal DA depletion. In adult animals, overlapping patches of leu-enkephalin- and SP-immunoreactive fibers were observed, regardless of whether any DA terminals remained. Thus, the basic organization of the striatal patch and matrix compartments develops normally in the absence of DA innervation through much of the formative period. Although these observations do not completely dismiss the possibility that the first DA afferents to appear in the striatal primordia influence contracted striatal cells to develop the patch phenotype, they suggest that the patchy distribution of DA afferents may be secondary to the early clustering of striatal neurons forming the patch compartment.
在大鼠产前后期和产后早期，黑质纹状体多巴胺（DA）投射终止于不同的斑块中。在出生后的第一周，DA纤维斑块与具有若干已确定特征的纹状体神经元簇重叠。纹状体细胞类型在这些斑块或周围基质中的早期分离成为纹状体的一个永久性组织特征。为了确定DA的异质分布是否影响细胞斑块的形成，在正常大鼠以及出生时（0或3天）或子宫内（胚胎第17 - 18天）DA耗尽的大鼠中，检查了化学可识别细胞类型的发育组织。在出生后的第一周，正常动物纹状体中存在相应的DA传入纤维斑块和P物质（SP）免疫反应性神经元，并且乙酰胆碱酯酶（AChE）阳性区在外侧纹状体与这些斑块重叠。向胎儿或新生大鼠侧脑室注射6 - 羟基多巴胺导致纹状体DA终末显著丧失。出生后前两周存在的SP免疫反应性神经元的斑块状分布或AChE染色的独特模式均未被破坏。在出生后的第三周，亮脑啡肽或钙结合蛋白 - D28k免疫反应性细胞局限于基质区室，并且这种区室化在产前或产后DA耗尽时也没有明显改变。在成年动物中，无论是否有任何DA终末残留，均观察到亮脑啡肽和SP免疫反应性纤维的重叠斑块。因此，在形成期的大部分时间里，在没有DA神经支配的情况下，纹状体斑块和基质区室的基本组织正常发育。尽管这些观察结果并未完全排除最初出现在纹状体原基中的DA传入纤维影响收缩的纹状体细胞以发展斑块表型的可能性，但它们表明DA传入纤维的斑块状分布可能继发于形成斑块区室的纹状体神经元的早期聚集。
