SYNAPTIC CONNECTIONS OF SPINAL CORD NEURONS

脊髓神经元的突触连接

• 批准号: 6637347
• 负责人: WILLIAM D WILLIS
• 金额: $ 37.25万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 1975
• 资助国家: 美国
• 起止时间: 1975-05-01 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6637347
• 关键词: AMPA receptors; Macaca fascicularis; NMDA receptors; behavior test; biological signal transduction; calmodulin dependent protein kinase; capsaicin; central neural pathway /tract; dorsal horn; electrophysiology; enzyme activity; enzyme inhibitors; excitatory aminoacid; gene expression; hyperalgesia; immunocytochemistry; laboratory rat; mesencephalon; microdialysis; neurons; phosphorylation; protein kinase; synapses; transcription factor; western blottings

The application is for renewal of a grant that has supported a long-term investigation of mechanisms of nociception and antinociception. The eventual goal of the proposed studies is to learn how plastic changes in nociceptive responses lead to persistent pain and to develop new approaches for chronic pain therapy. The overall hypothesis of the present proposal is that nociceptive transmission in the spinal cord is regulated by protein kinases and phosphatases through phosphorylation and dephosphorylaion of synaptic receptors and of proteins involved in intracellular signal transduction pathways. The outcome of this regulation can be central sensitization (or conversely, long-lasting inhibition) of nociceptive neurons, such as spinothalamic tract (STT) cells, as well as changes in gene expression in nociceptive neurons. Central sensitization, which has been suggested to underlie secondary allodynia and hyperalgesia, is proposed to depend at least in part on postsynaptic changes in STT cells. Specific Aim 1 is to determine if different protein kinases are activated in STT cells and if different protein kinases contribute to differences in the responses of STT cells to innocuous and noxious stimuli, leading to different balances of allodynia and hyperalgesia. Specific Aim 2 is to determine if the induction of central sensitization, like long-term potentiation, depends on the activation of calmodulin and calcium/calmodulin-dependent kinase II (CaMKII). Specific Aim 3 is to determine if phosphorylation of amino acid receptors occurs in STT cells during central sensitization and to investigate how inhibition of CaMKII permits the expression of along-lasting inhibition. Specific Aim 4 is to determine if agents that alter central sensitization also alter the expression of inducible immediate, early genes and phosphorylation of constitutive transcription factors. The experimental approaches that will be used include the analysis of behavioral changes, electrophysiological recordings and pharmacological modulation of proteins involved in nociceptive signal transduction, and immunohistochemical and Western blotting studies, using antibodies to non-phosphorylated and phosphorylated proteins that contribute to the structure of glutamate receptors or belong to signal transduction pathways.

该申请旨在续签一项资助，该资助支持对伤害感受和抗伤害机制的长期研究。拟议研究的最终目标是了解伤害性反应的可塑性变化如何导致持续性疼痛，并开发慢性疼痛治疗的新方法。本提议的总体假设是，脊髓中的伤害性传递是由蛋白激酶和磷酸酶通过突触受体和参与细胞内信号转导途径的蛋白质的磷酸化和去磷酸化来调节的。这种调节的结果可能是伤害性神经元（例如脊髓丘脑束（STT）细胞）的中枢敏化（或相反，长期抑制），以及伤害性神经元基因表达的变化。中枢敏化被认为是继发性异常性疼痛和痛觉过敏的基础，并且被认为至少部分取决于 STT 细胞的突触后变化。具体目标 1 是确定 STT 细胞中是否激活了不同的蛋白激酶，以及不同的蛋白激酶是否导致 STT 细胞对无害和有害刺激的反应差异，从而导致异常性疼痛和痛觉过敏的不同平衡。具体目标 2 是确定中枢敏化的诱导（如长时程增强）是否取决于钙调蛋白和钙/钙调蛋白依赖性激酶 II (CaMKII) 的激活。具体目标 3 是确定 STT 细胞在中枢致敏过程中是否发生氨基酸受体磷酸化，并研究 CaMKII 的抑制如何允许持久抑制的表达。具体目标 4 是确定改变中枢敏化的药物是否也会改变诱导型即时、早期基因的表达和组成型转录因子的磷酸化。将使用的实验方法包括分析行为变化、电生理记录和参与伤害性信号转导的蛋白质的药理学调节，以及免疫组织化学和蛋白质印迹研究，使用有助于谷氨酸结构的非磷酸化和磷酸化蛋白质的抗体受体或属于信号转导途径。