Qu S, Ondo W G, Zhang X, Xie W J, Pan T H, Le W D
Department of Neurology, Baylor College of Medicine, 6501 Fannin Street, NB205, Houston, TX 77030, USA.
Exp Brain Res. 2006 Jan;168(1-2):152-6. doi: 10.1007/s00221-005-0075-1. Epub 2005 Jul 26.
The aim of this study is to investigate the pathway of diencephalic dopaminergic (DA) neuronal innervating into the spinal cord in mice, the pathway is postulated relevant to clinical restless legs syndrome (RLS). Tyrosine hydroxylase (TH) immunohistochemistry was used to identify the DA neuron. The fluorescent tracer Fluoro-Gold (FG) was stereotaxically injected into the T10-L5 spinal cord of CBL57 mice (n=20) seven days before the animals were sacrificed. The diencephalic sections were stained with TH antibody and the FG tracer present in the diencephalic DA neurons were examined under fluoresce microscope. The average number of total DA neurons per side in A11, A12, A13 and A14 was 66+/-8, 221+/-12, 350+/-17 and 254+/-21 respectively. After being injected into the spinal cord, FG reached the DA neurons within the A10 and A11 groups, but didn't target to any other DA neuron groups including the A8 and A9 groups in substantia nigra (SN). The diencephalic A11 DA neurons possessed long axons extending over several segments and possibly traversing the entire length of the spinal cord. It is the first time to report A10 and A11 DA neuron projections into the spinal cord in mice.
本研究旨在探究小鼠中脑多巴胺能（DA）神经元支配脊髓的通路，该通路被认为与临床不宁腿综合征（RLS）相关。采用酪氨酸羟化酶（TH）免疫组织化学法鉴定DA神经元。在处死动物前7天，将荧光示踪剂氟金（FG）立体定向注射到CBL57小鼠（n = 20）的T10 - L5脊髓中。用TH抗体对间脑切片进行染色，并在荧光显微镜下检查间脑DA神经元中存在的FG示踪剂。A11、A12、A13和A14每侧DA神经元总数的平均值分别为66±8、221±12、350±17和254±21。注入脊髓后，FG到达A10和A11组内的DA神经元，但未靶向包括黑质（SN）中的A8和A9组在内的任何其他DA神经元组。间脑A11 DA神经元具有延伸多个节段的长轴突，可能贯穿脊髓全长。这是首次报道小鼠中A10和A11 DA神经元向脊髓的投射。
