Responses of dorsal root ganglion cells to increased and decreased neuromuscular activity

体力活动增加和减少对感觉神经特性的影响知之甚少。建议的研究计划将检查每天增加(跑步机训练和自愿车轮运动)或减少(单侧后肢瘫痪和后肢悬吊模拟失重)每日神经肌肉活动1个月的大鼠后肢机械感受器所支配的大型感觉细胞。在背根神经节细胞中测量的特性包括它们的电生理特性和离子电流密度，编码神经营养因子和离子通道亚单位的基因的表达，它们对急性电刺激的代谢信号反应，以及它们与脊髓中阿尔法运动神经元的突触效力。可以使用的技术范围从电生理到免疫组织化学，再到用于检测基因表达变化的程序。这些实验产生的信息将为我们检查身体活动对其他类型的感觉细胞的影响，如疼痛传入，以及在更复杂的系统，如大脑和脊髓，提供一些指导。

Very little is known as to the effects of increased and decreased physical activity on the properties of sensory nerves.  The proposed research program will examine the large sensory cells innervating mechanoreceptors in the hindlimbs of rats exposed to 1 month of increased (treadmill training and voluntary wheel exercise) or decreased (unilateral hindlimb paralysis and simulated weightlessness via hindlimb suspension) daily neuromuscular activity.  Properties to be measured in dorsal root ganglion cells include their electrophysiological properties and ion current densities, the expression of genes coding for neurotrophic factors and ion channel subunits, their metabolic signaling responses to acute electrical stimulation, and their synaptic efficacy with alpha-motoneurones in spinal cord.  Techniques to be used range from electrophysiological to immunohistochemical, and on to procedures used to detect changes in gene expression.  The information emanating from these experiments will give us some direction in examining physical activity effects on other types of sensory cells, such as pain afferents, and in more complex systems, such as brain and spinal cord.