PHYSIOLOGICAL CORRELATES OF COLLATERAL SPROUTING

这项研究的长期目标是了解 部分脱位后脊髓功能的恢复。这个 潜伏性突触与功能恢复的关系将通过 比较正常人和正常人对皮肤和神经刺激的反应 去传入的动物。侧枝萌发在中介中的作用 损伤后对高阈值刺激的反应增加 正常个体高阈值传入神经元的HRP标记 和部分去传入的动物。假设一些损失和损失 损伤后的功能恢复可以用一过性的 将通过记录电信号来测试突触传递的故障 背角神经元的特性与兴奋性有关。分析将 是利用神经细胞群体进行的，这些神经细胞的特性已经 在正常动物中有很好的特点，即起源于 脊髓颈束和高阈值A-三角区机械感受性传入 纤维。要使用的方法包括细胞内和细胞外 颈脊髓束神经元的电生理记录 猫急、慢性背根和周围神经损伤。 对皮肤的机械刺激和电刺激的反应 将对神经刺激进行评估。急性损伤的影响将 与可逆性神经、背部传导阻滞的比较 树根。这些研究与预防的健康目标有关。 周围神经或脊髓损伤后的残疾和康复 患有慢性脊髓或周围神经损伤的个人。

The long term objectives of this research are to understand the bases of recovery of function in the spinal cord following partial devervation. The relationship of latent synapses to recovery of function will be studied by comparing response to cutaneous and nerve stimulation in normal and deafferented animals. The role of collateral sprouting in mediating increased responses to high threshold stimuli following lesions will be assessed by HRP labelling of individual high-threshold afferents in normal and partially deafferented animals. The hypothesis that some loss and recovery of function following lesions can be accounted for by a transient failure of synaptic transmission will be tested by recording electrical properties of dorsal horn neurons related to excitability. Analysis will be carried out using populations of nerve cells whose properties have been well characterized in normal animals, namely, the cells of origin of the spinocervical tract, and high-threshold A-delta mechanoreceptive afferent fibers. The methods to be used include intra- and extracellular electrophysiological recording from spinocervical tract neurons following acute and chronic dorsal root and peripheral nerve lesions in cats. Responses to both mechanical stimulation of the skin and electrical stimulation of nerves will be evaluated. The effects of acute injury will be compared with those of reversible conduction block of nerves and dorsal roots. These studies are related to the health goals of preventing disability following peripheral nerve or spinal injury, and rehabilitating individuals with chronic spinal cord or peripheral nerve lesions.