Rotto-Percelay D M, Wheeler J G, Osorio F A, Platt K B, Loewy A D
Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110.
Brain Res. 1992 Mar 6;574(1-2):291-306. doi: 10.1016/0006-8993(92)90829-x.
The distribution of retrogradely and transneuronally labeled neurons was studied in CNS of rats 4 days after injections of the Bartha strain of pseudorabies virus (PRV) into the medial gastrocnemius (MG) muscle. Tissue sections were processed for immunohistochemical detection of PRV. Retrogradely labeled cells were identified in the ipsilateral MG motor column in the caudal L4 and the L5 spinal segments. In order to evaluate the efficacy of PRV retrograde cell body labeling, the number of PRV retrogradely labeled neurons in the MG motor column was compared to the number labeled with two conventional retrograde cell body markers--Fluoro-Gold and cholera toxin-HRP. A ratio of 1:3 representing medium-sized (less than 30 microns) versus large neurons (greater than 30 microns) was found in the Fluoro-Gold dye experiments; a 1:2 ratio was seen in the PRV experiments. In contrast, when cholera toxin-HRP was used as a retrograde marker, mainly large neurons were labeled; the medium-to-large cell body ratio was 1:10 suggesting cholera toxin-HRP may have a greater affinity for the terminals of alpha-motoneurons as opposed to gamma-motoneurons. Transneuronally labeled cells were identified in the L1-L6 spinal gray matter, intermediolateral cell column (T11-L2), lateral spinal nucleus and medial part of lamina VII in C4 and C5 spinal segments, brainstem (caudal raphe nuclei, rostral ventrolateral medulla, A5 cell group, paralemniscal nucleus, locus coeruleus, subcoeruleus nucleus, red nucleus) and paraventricular hypothalamic nucleus. In the L5 spinal cord, transneuronally labeled neurons were seen in the ipsilateral spinal laminae I and II and bilaterally in spinal laminae IV-VIII, and X. Similar results were obtained in rats that had chronic unilateral L3-L6 dorsal rhizotomies indicating most of the labeling was due to retrograde transneuronal cell body labeling. In order to determine whether PRV was transported into the spinal cord by the dorsal root axons, the ipsilateral dorsal root ganglia (DRGs) were examined for PRV immunoreactivity; none was found. However, using the polymerase chain reaction, viral DNA was shown to be present in the ipsilateral DRGs indicating that some of spinal cord cell body labeling may have resulted from anterograde transneuronal labeling, as well.
将伪狂犬病病毒（PRV）Bartha株注射到大鼠的腓肠肌内侧（MG）4天后，研究了逆行和顺行跨神经元标记神经元在大鼠中枢神经系统中的分布。对组织切片进行处理以免疫组织化学检测PRV。在尾侧L4和L5脊髓节段的同侧MG运动柱中鉴定出逆行标记的细胞。为了评估PRV逆行标记细胞体的效果，将MG运动柱中PRV逆行标记神经元的数量与用两种传统逆行细胞体标记物——荧光金和霍乱毒素-HRP标记的数量进行比较。在荧光金染料实验中发现中型（小于30微米）与大型神经元（大于30微米）的比例为1:3；在PRV实验中为1:2。相比之下，当使用霍乱毒素-HRP作为逆行标记物时，主要标记大型神经元；中型与大型细胞体的比例为1:10，表明霍乱毒素-HRP对α运动神经元的终末可能比对γ运动神经元具有更大的亲和力。在L1-L6脊髓灰质、中间外侧细胞柱（T11-L2）、外侧脊髓核以及C4和C5脊髓节段的VII层内侧部分、脑干（尾侧中缝核、嘴侧腹外侧延髓、A5细胞群、旁臂旁核、蓝斑、蓝斑下核、红核）和下丘脑室旁核中鉴定出顺行跨神经元标记的细胞。在L5脊髓中，同侧脊髓I层和II层以及双侧脊髓IV-VIII层和X层中可见顺行跨神经元标记的神经元。在患有慢性单侧L3-L6背根切断术的大鼠中也获得了类似的结果，表明大多数标记是由于逆行跨神经元细胞体标记。为了确定PRV是否通过背根轴突运输到脊髓，检查同侧背根神经节（DRG）的PRV免疫反应性；未发现。然而，使用聚合酶链反应，显示病毒DNA存在于同侧DRG中，表明脊髓细胞体标记中的一些也可能是由于顺行跨神经元标记所致。
