Cliffer K D, Giesler G J
Department of Cell Biology and Neuroanatomy, University of Minnesota, Minneapolis 55455.
J Neurosci. 1989 Sep;9(9):3146-68. doi: 10.1523/JNEUROSCI.09-09-03146.1989.
The distribution in the dorsal column nuclei (DCn) of post-synaptic dorsal column (PSDC) fibers was examined in rats following injections of Phaseolus vulgaris leucoagglutinin (PHA-L) in the spinal cord. Lemniscal neurons in the DCn were retrogradely labeled in the same animals by injecting the thalamus with Fluoro-Gold. In some experiments, primary afferent fibers were also labeled by injecting dorsal root ganglia with choleragenoid-conjugated HRP. Injections of PHA-L into the cervical enlargement labeled many fibers and varicosities throughout most of the ipsilateral cuneate nucleus. Labeled fibers were also present in the external cuneate and internal basilar nuclei. Injections of PHA-L into thoracic cord labeled fibers and varicosities in the medial cuneate and lateral gracile nuclei, as well as the external cuneate nucleus. Injections into the lumbar enlargement labeled fibers and varicosities throughout most of the gracile nucleus. Injections in sacral cord labeled fibers in the most medial part of the gracile nucleus. Dense labeling of PSDC fibers was found in areas with high densities of retrogradely labeled lemniscal neurons and areas with high densities of primary afferent fibers. In all regions of the DCn and in the external cuneate nucleus, fibers and varicosities labeled for PHA-L were seen in apposition to retrogradely labeled lemniscal cells. The distribution of postsynaptic afferent fibers in the DCn of the rat and its relationship to lemniscal neurons and primary afferent fibers contrast sharply with these features in cats.
在大鼠脊髓注射菜豆白细胞凝集素（PHA-L）后，研究了脊髓后角突触后纤维在背柱核（DCn）中的分布。通过向丘脑注射荧光金，在同一只动物中逆行标记DCn中的薄束核神经元。在一些实验中，还通过向背根神经节注射霍乱毒素结合的辣根过氧化物酶（HRP）来标记初级传入纤维。向颈膨大注射PHA-L可标记同侧楔束核大部分区域的许多纤维和曲张体。标记纤维也存在于楔外侧核和基底内侧核。向胸段脊髓注射PHA-L可标记内侧楔束核、外侧薄束核以及楔外侧核中的纤维和曲张体。向腰膨大注射PHA-L可标记薄束核大部分区域的纤维和曲张体。向骶段脊髓注射PHA-L可标记薄束核最内侧部分的纤维。在逆行标记的薄束核神经元高密度区域和初级传入纤维高密度区域发现了密集标记的脊髓后角突触后纤维。在DCn的所有区域以及楔外侧核中，可见标记PHA-L的纤维和曲张体与逆行标记的薄束核细胞相邻。大鼠DCn中突触后传入纤维的分布及其与薄束核神经元和初级传入纤维的关系与猫的这些特征形成鲜明对比。
