Neuroscience Research Australia, Randwick, NSW, 2031, Australia.
Brain Struct Funct. 2012 Apr;217(2):211-9. doi: 10.1007/s00429-011-0337-6. Epub 2011 Jul 7.
The mesencephalic locomotor region (MLR) plays an important role in the control of locomotion, but there is ongoing debate about the anatomy of its connections with the spinal cord. In this study, we have examined the spinal projections of the mouse precuneiform nucleus (PrCnF), which lies within the boundaries of the presumptive MLR. We used both retrograde and anterograde labeling techniques. Small clusters of labeled neurons were seen in the medial portion of the PrCnF following fluoro-gold injections in the upper cervical spinal cord. Fewer labeled neurons were seen in the PrCnF after upper thoracic injections. Following the injection of anterograde tracer (biotinylated dextran amine) into the PrCnF, labeled fibers were clearly observed in the spinal cord. These fibers traveled in the ventral and lateral funiculi, and terminated mainly in the medial portions of laminae 7, 8, and 9, as well as area 10, with an ipsilateral predominance. Our observations indicate that projections from the PrCnF to the spinal cord may provide an anatomical substrate for the role of the MLR in locomotion.
中脑运动区（MLR）在运动控制中起着重要作用，但关于其与脊髓的连接解剖结构仍存在争议。在这项研究中，我们研究了位于假定的 MLR 边界内的小鼠楔前核（PrCnF）的脊髓投射。我们使用了逆行和顺行标记技术。在颈上脊髓注射荧光金后，在 PrCnF 的内侧部分观察到少量标记神经元。在上胸段注射后，PrCnF 中的标记神经元较少。在将顺行示踪剂（生物素化葡聚糖胺）注入 PrCnF 后，在脊髓中可以清楚地观察到标记纤维。这些纤维在腹侧和外侧束中行进，并主要终止于第 7、8 和 9 层的内侧部分以及 10 区，以同侧为主。我们的观察表明，来自 PrCnF 的投射到脊髓可能为 MLR 在运动中的作用提供解剖学基础。
