NEURONAL PLASTICITY IN ALS SPINAL CORD NEURONS

这项提案的目的是研究神经可能参与 生长因子（NGF）在下运动神经元功能中的作用， 该因子可能在脊髓运动神经元去神经支配中起作用， 肌萎缩侧索硬化症（ALS）的神经再支配。 最近有人 显示脊髓中α运动神经元表达NGF受体 信使RNA（mRNA）和蛋白质在发育过程中， 周围神经损伤 神经生长因子受体似乎是必不可少的， 启动NGF的生物学作用。 这些研究表明 脊髓和可能的脑干运动神经元有能力 对NGF的反应。 使用放射性NGF受体cRNA探针 用原位杂交组织化学方法， ALS死后脊髓组织中运动神经元表达的证据 NGF受体的mRNA。 此外，我们的数据表明，NGF受体 mRNA表达优先发生在脊髓节段相关 临床肌肉萎缩（肌无力、萎缩等）。我们 假设随着疾病的发展，一些运动神经元开始 重新表达与生长相关的蛋白质， 进行性退化状态 有趣的是，肌电图证据表明， 脊髓运动神经元功能性再神经支配是常见的， 失神经肌肉，虽然这种新的增长可能最终会失去， 好. 此外，脊髓中的一组运动神经元， 在ALS（Onufrowicz核）中出现退化， 在成年实验动物中表达NGF受体。 不像其他 脊髓运动神经元，这些神经元可能维持 在整个成年生活中对NGF的反应能力。 我们建议研究 生长相关蛋白（即NGF受体和 GAP-43）。 我们将使用原位杂交技术 组织化学、免疫细胞化学和RNA保护测定，以鉴定 NGF受体和GAP-43表达的变化。 此外，我们将 试图将这些变化与退化程度（通过 尼氏染色和银染色）与每种ALS的临床病史 病人 在本申请中提出的实验将提供一个 更好地理解与癌症相关的细胞和分子事件， 肌萎缩侧索硬化脊髓的失神经-神经再支配，以及神经元的可塑性， CNS。

The goal of this proposal is to study the possible involvement of nerve growth factor (NGF) in lower motor neuron function, and to evaluate the role this factor may play in spinal cord motor neuron denervation- reinnervation in amyotrophic lateral sclerosis (ALS). It has recently been shown that alpha motor neurons in spinal cord express NGF receptor messenger RNA (mRNA) and protein during development and in response to peripheral nerve damage. NGF receptors appear to be essential for the initiation of the biological actions of NGF. These studies indicate that spinal cord, and possibly brain stem motor neurons have the capacity to respond to the actions of NGF. Using a radioactive NGF receptor cRNA probe with in situ hybridization histochemistry, we have obtained preliminary evidence that motor neurons in ALS postmortem spinal cord tissue express mRNA for NGF receptor. In addition, our data indicate that NGF receptor mRNA expression occurs preferentially in spinal cord segments associated with clinical symptomatology (muscle weakness, atrophy, etc.). We hypothesize that as the disease process advances, some motor neurons start to reexpress growth related proteins in an attempt to compensate for the progressive degenerative state. Interestingly, EMG evidence indicates that it is common for spinal cord motor neurons to functionally reinnervate denervated muscles, although this new growth may ultimately be lost as well. Further, one set of motor neurons in the spinal cord that do not appear to degenerate in ALS (Onufrowicz's nucleus) have recently been shown to express NGF receptors in adult experimental animals. Unlike other spinal cord motor neurons, it is possible that these neurons maintain the capacity to respond to NGF throughout adult life. We propose to study the potential expression of growth-related proteins (i.e. NGF receptor and GAP-43) in ALS spinal cord tissue. We will use in situ hybridization histochemistry, immunocytochemistry, and RNA protection assays to identify changes in the expression of NGF receptor and GAP-43. In addition, we will attempt to correlate these changes and the degree of degeneration (through the use of Nissl and silver stains) with the clinical history of each ALS patient. The experiments proposed in this application will provide a better understanding of the cellular and molecular events associated with denervation-reinnervation in ALS spinal cord, and of neuronal plasticity in the CNS.