Yoshida A, Tsuru K, Mitsuhiro Y, Otani K, Shigenaga Y
Brain Res. 1987 Jul 28;416(2):393-401. doi: 10.1016/0006-8993(87)90925-5.
Masticatory motoneurons were identified electrophysiologically and stained with horseradish peroxidase (HRP). The masseter motoneurons could be divided into 3 groups on the basis of their dendritic morphology. In contrast, the digastric or mylohyoid motoneurons showed a similar dendritic configuration. These neurons had much developed dendritic trees in the dorsomedial than ventrolateral direction. The first group of the masseter motoneurons had their dendritic trees which extended radially in all directions with a slight preference to project rostrally. These somata were located in the center of the subdivision containing the masseter motoneurons. In the second group, their dendritic arbores had a polarity extending hemispherically. These neuronal somata were located in the medial, ventral, and lateral regions of the subdivision. For the masseter motoneurons in the two groups and jaw-opening motoneurons, the dendritic swellings were frequently observed in the distal branches. The third group had their dendritic trees which were much simpler in configurations with less tapering or branching than those of other neurons examined. Furthermore, a wide variety of dendritic spines and appendages, and no dendritic swellings, observed in the third group were distinct from other neurons stained. The dendritic trees of the jaw-closing and -opening motoneurons were confined to the individual subdivisions. There were no instances in which axon collaterals were observed for well-stained 16 axons.
咀嚼运动神经元通过电生理方法进行鉴定，并用辣根过氧化物酶（HRP）进行染色。咬肌运动神经元可根据其树突形态分为3组。相比之下，二腹肌或下颌舌骨肌运动神经元则呈现出相似的树突结构。这些神经元的树突在背内侧方向比腹外侧方向更为发达。第一组咬肌运动神经元的树突向各个方向呈放射状延伸，略倾向于向前延伸。这些胞体位于包含咬肌运动神经元的亚区中心。在第二组中，它们的树突分支具有半球形延伸的极性。这些神经元胞体位于亚区的内侧、腹侧和外侧区域。对于这两组中的咬肌运动神经元和开颌运动神经元，在远端分支中经常观察到树突膨大。第三组的树突结构要简单得多，与其他所检查的神经元相比，其变细或分支较少。此外，在第三组中观察到的各种各样的树突棘和附属物以及没有树突膨大的情况，与其他染色的神经元明显不同。闭颌和开颌运动神经元的树突局限于各自的亚区。在16条染色良好的轴突中，没有观察到轴突侧支的情况。
