Eccles J C, Rantucci T, Scheid P, Táboríková H
J Neurophysiol. 1975 Jul;38(4):965-80. doi: 10.1152/jn.1975.38.4.965.
The somatotopic inputs into red nucleus (RN) neurons have been studied with special reference to their level of projection in the spinal cord. As inputs we employed either volleys in predominantly cutaneous nerves of forelimb and hindlimb or cutaneous mechanoreceptor discharges evoked by taps to footpads of forelimb and hindlimb. There has been physiological confirmation of the anatomical findings that RD neurons projecting to the lumbar cord are located in the ventrolateral zone of the pars magnocellularis, whereas in the dorsomedial zone are RN neurons with cervical but not lumbar projection. Somatotopically there was found to be a differentiation of input to RN neurons according as they projected to the lumbar or only to the cervical cord. This finding was presented in the form both of tables and of somatotopic maps. As expected, this discrimination was more restrictive for the more selective inputs from pad taps than for nerve inputs. Nevertheless, forelimb inputs often had a considerable excitatory and inhibitory action on lumbar-projecting RN neurons, and vice versa for cervical-projecting neurons. There were two notable somatotopic findings that suggest specificities of connectivities. First, despite the large convergence of IP neurons onto RN neurons (about 50-fold), the degree of somatotopic discrimination was about the same for interpositus and RN neurons with two testing procedures: between inputs from forelimb and hindlimb; and between inputs from pads on one foot. Second, although there was in the interpositus nucleus a considerable topographical admixture of neurons with dominant forelimb or hindlimb inputs, the axonal projections of these neurons were apparently unscrambled on the way to the target RN neurons, so as to deliver the somatotopic specificities observed for two classes of RN neurons; those projecting down the spinal cord beyond L2 level, and those projecting to C2 but not L2. Finally, there is a general discussion of motor control with reference to the pathway; pars intermedia of anterior lobe of cerebellum leads to interpositus nucleus leads to red nucleus leads to rubrospinal tract leads to spinal motoneurons.
对红核（RN）神经元的躯体定位输入进行了研究，特别关注其在脊髓中的投射水平。作为输入，我们采用了前肢和后肢主要皮神经中的群集放电，或者通过轻敲前肢和后肢脚垫诱发的皮肤机械感受器放电。解剖学研究发现，投射到腰髓的红核神经元位于大细胞部的腹外侧区，而投射到颈髓而非腰髓的红核神经元位于背内侧区，这一发现已得到生理学证实。从躯体定位角度来看，发现投射到腰髓或仅投射到颈髓的红核神经元的输入存在差异。这一发现以表格和躯体定位图的形式呈现。正如预期的那样，这种区分对于来自脚垫轻敲的更具选择性的输入比神经输入更为严格。然而，前肢输入通常对投射到腰髓的红核神经元有相当大的兴奋和抑制作用，反之，对于投射到颈髓的神经元，后肢输入也有类似作用。有两个显著的躯体定位研究发现表明了连接的特异性。首先，尽管中间神经元（IP）对红核神经元有大量汇聚（约50倍），但在两种测试程序下，中间神经元和红核神经元的躯体定位区分程度大致相同：在前肢和后肢输入之间；以及在一只脚上的脚垫输入之间。其次，尽管在中间核中，具有主要前肢或后肢输入的神经元存在相当大的地形混合，但这些神经元的轴突投射在通往目标红核神经元的途中显然没有混淆，从而传递了在两类红核神经元中观察到的躯体定位特异性；一类投射到脊髓L2水平以下，另一类投射到C2但不投射到L2。最后，结合该通路对运动控制进行了一般性讨论；小脑前叶中间部通向中间核，中间核通向红核，红核通向红核脊髓束，红核脊髓束通向脊髓运动神经元。
