Kitamura S, Nishiguchi T, Sakai A
Exp Neurol. 1985 Jan;87(1):20-34. doi: 10.1016/0014-4886(85)90130-x.
The peripheral course of axons of rat lingual motoneurons was studied by HRP injection into the hypoglossal nerve in combination with transecting of the hypoglossal and/or cervical nerve components of the hypoglossocervical plexus. Furthermore, soma sizes of labeled lingual motoneurons were compared in transverse section with those of labeled geniohyoid and thyrohyoid motoneurons, which are situated adjacent to the lingual motoneurons. We found that axons of the majority of lingual motoneurons lying in the main hypoglossal nucleus passed through the hypoglossal nerve throughout their course to the tongue. In a remaining small number of lingual motoneurons lying in a medial portion of the ventromedial subnucleus in the caudal fourth of the main hypoglossal nucleus, their axons passed through the first cervical nerve to the upper root of the ansa cervicalis to the hypoglossal nerve and then to its medial branch. The labeled lingual motoneurons with axons passing through the cervical nerve were intermingled with those whose axons passed through the hypoglossal nerve. The latter motoneurons, however, diminished in number while being traced caudally, and finally in the most caudal main hypoglossal nucleus the former motoneurons occupied a major part of this nucleus. The lingual motoneurons with axons passing through the cervical nerve were smaller in soma size than those with axons passing through the hypoglossal nerve. These two types of lingual motoneurons were both smaller in soma size than the geniohyoid and thyrohyoid motoneurons, and their soma shape was not as flat as that of the latter types of motoneurons.
通过将辣根过氧化物酶（HRP）注入舌下神经，并结合切断舌下神经颈丛的舌下神经和/或颈神经成分，研究了大鼠舌运动神经元轴突的外周行程。此外，在横切面上比较了标记的舌运动神经元与位于舌运动神经元附近的标记的颏舌骨肌和甲状舌骨肌运动神经元的胞体大小。我们发现，大多数位于舌下神经主核的舌运动神经元的轴突在其通向舌头的整个行程中都穿过舌下神经。在舌下神经主核尾侧四分之一的腹内侧亚核内侧部分的少数剩余舌运动神经元中，它们的轴突穿过第一颈神经至颈袢上根，再至舌下神经，然后至其内侧支。轴突穿过颈神经的标记舌运动神经元与轴突穿过舌下神经的舌运动神经元相互交织。然而，后者的运动神经元数量在向尾侧追踪时减少，最终在最尾侧的舌下神经主核中，前者的运动神经元占据了该核的大部分。轴突穿过颈神经的舌运动神经元的胞体大小比轴突穿过舌下神经的舌运动神经元小。这两种类型的舌运动神经元的胞体大小均比颏舌骨肌和甲状舌骨肌运动神经元小，并且它们的胞体形状不如后一种类型的运动神经元扁平。
