Alvarez F J, Dewey D E, Carr P A, Cope T C, Fyffe R E
Department of Anatomy, Wright State University, Dayton, Ohio 45435, USA.
Neuroreport. 1997 May 6;8(7):1711-6. doi: 10.1097/00001756-199705060-00029.
Axotomized motoneurons display drastic modifications in synaptic structure and function related to their disconnection from the periphery and establishment of a regenerative metabolic functional mode. The molecular basis of these modifications is not fully understood. Here we describe changes in metabotropic glutamate receptor 1a (mGluR1a)-immunoreactivity 3, 7 or 14 days after unilateral aciatic transection. mGluR1a-immunoreactivity was distributed throughout the somatic cytoplasm and somatodendritic membrane of uninjured motoneurons and was significantly reduced in axotomized motoneurons. This reduction was observed at 3 days and grew progressively over 2 weeks. These findings suggest that downregulation of mGluR1a could contribute to reduced excitatory neurotransmission in axotomized motoneurons.
轴突切断的运动神经元在突触结构和功能上表现出剧烈变化，这与其与外周的断开连接以及再生代谢功能模式的建立有关。这些变化的分子基础尚未完全明确。在此，我们描述了单侧坐骨神经横断后3天、7天或14天代谢型谷氨酸受体1a（mGluR1a）免疫反应性的变化。mGluR1a免疫反应性分布于未受损运动神经元的整个体细胞胞质和体树突膜，而在轴突切断的运动神经元中显著降低。这种降低在3天时即可观察到，并在2周内逐渐加剧。这些发现表明，mGluR1a的下调可能导致轴突切断的运动神经元兴奋性神经传递减少。
