Reinnervation by axon collaterals from single facial motoneurons to multiple muscle targets following axotomy in the adult guinea pig.
Reinnervation by axon collaterals from single facial motoneurons to multiple muscle targets following axotomy in the adult guinea pig.
复制标题
成年豚鼠轴突切除术后，轴突侧枝从单个面部运动神经元到多个肌肉目标的神经再支配。
DOI：
--
复制
发表时间：
1994
期刊：
影响因子：
--
通讯作者：
M. Kudo
中科院分区：
文献类型：
--
作者：
M. Ito;M. Kudo
为了实验研究面瘫的恢复过程，采用双标记法，用两种逆行示踪剂检测了面神经手术损伤的成年豚鼠二腹肌后腹和面神经干颞外部分的颅运动神经元的位置。在诱导面神经麻痹功能恢复后的不同阶段（术后4 ~ 13周），将小麦胚芽凝集的辣根过氧化物酶（WGA-HRP）注射于面神经干颞外部分近端切割处，荧光ruby （FR）涂于面神经干颞外部分近端。绘制WGA-HRP和/或FR逆行标记的神经元在脑干中的分布，并与对照组进行比较。在完整的病例中，hrp标记的神经元局限于面部副核（Acs7），而fr标记的神经元位于面部主核（FMN）。(1)在Acs7和FMN中可以看到弥漫性的hrp标记的神经元，在那里正常的肌外源性表征似乎不再维持。(2) FMN和Acs7中也弥漫性观察到fr标记的神经元。(3)存活时间较短（4-7周）的Acs和FMN中有相当数量的神经元双标记WGA-HRP和FR，而存活时间较长的（12-13周）则没有。因此，新的研究结果表明，在成年哺乳动物中，单个面部运动神经元与轴突侧支与多个肌肉靶点的连接是暂时维持的。（摘要删节250字）
To study the process of recovery from facial palsy experimentally, the location of cranial motoneurons supplying the posterior belly of the digastric muscle (PDG) and the extratemporal portion of the facial nerve trunk was examined in a double-labeling paradigm using two retrograde tracers in the adult guinea pig of which the facial nerve had been surgically injured. In different stages after the induced facial palsy had recovered functionally (4-13 weeks after the surgical operation), wheat germ-agglutinated horseradish peroxidase (WGA-HRP) was injected into the PDG and Fluoro-Ruby (FR) was applied to the proximal cut end of the extratemporal portion of the facial nerve trunk. Distribution of neurons retrogradely labeled with WGA-HRP and/or FR was plotted in the brainstem and compared with that of the controls. In the intact cases, HRP-labeled neurons were restrictedly seen in the accessory facial nucleus (Acs7), while FR-labeled neurons were found within the main facial nucleus (FMN). In the axotomized cases: (1) HRP-labeled neurons were seen diffusely in the Acs7 as well as in the FMN, where normal myotopical representation no longer seemed to be maintained. (2) FR-labeled neurons were also observed diffusely in the FMN and the Acs7. (3) A considerable number of neurons were doubly labeled with WGA-HRP and FR in both the Acs and the FMN in cases with shorter survival periods (4-7 weeks), but not in cases with longer survival periods (12-13 weeks). Thus, new findings show that connections are temporarily maintained by single, facial motoneurons with axon collaterals to multiple muscle targets in adult mammals.(ABSTRACT TRUNCATED AT 250 WORDS)