Development of a Mouse Trigeminal Pain Model

描述（由申请人提供）：研究和治疗三叉神经疼痛障碍的主要挑战是缺乏适当的动物模型。虽然最初的触发事件是不同的，往往是神秘的，许多疾病的共同主题是参与神经肽CGRP。在这个R21项目中，我建议测试的假设，在小鼠三叉神经节的CGRP过表达将导致行为的变化，伤害性感受的指示。该方法将涉及将重组病毒递送到三叉神经节，然后进行功能测定。我们将使用鼻内给药靶向三叉神经，三叉神经支配鼻粘膜。该途径的优点是它应将病毒递送至整个三叉神经，包括眼分支和CNS的连接部分，同时限制对病毒载体的全身暴露。结合使用四环素调控的启动子系统，这种方法将允许相对局部化和急性表达，这将最大限度地减少补偿和系统性影响，可能会发生一个更全面的转基因方法。重要的是，病毒方法也将使我们更容易测试不同的遗传背景，包括具有额外神经元CGRP受体亚基的转基因小鼠。目的1建立并优化鼻内病毒载体技术，并研究具有生物活性的CGRP的表达。目的2将涉及一个热敏感性测定和两个厌恶行为测定作为是否过度表达三叉神经CGRP模拟某些三叉神经疼痛状态的初始测试。该提案的优势在于其多学科方法将涉及一组在CGRP基因表达，鼻内递送，伤害感受和小鼠行为方面具有专业知识的研究人员。从长远来看，这些研究将可能为偏头痛和颞下颌关节疾病等三叉神经介导的病理机制研究和治疗策略提供基础。三叉神经疼痛障碍的患病率和严重程度是一个重要的健康问题。由于偏头痛和所有类型的三叉神经痛的当前治疗的高发病率和通常差的功效，需要改进的治疗和预防措施。三叉神经介导的疼痛障碍的小鼠模型的开发将潜在地为测试药物和治疗性基因转移策略对三叉神经介导的偏头痛等病症的疗效提供基础。

DESCRIPTION (provided by applicant): A major challenge for studying and treating trigeminal pain disorders is the lack of appropriate animal models. While the initial triggering events are different and often cryptic, a common theme for many of the disorders is involvement of the neuropeptide CGRP. In this R21 project, I propose to test the hypothesis that overexpression of CGRP in the mouse trigeminal ganglion will lead to behavioral changes indicative of nociception. The approach will involve delivery of recombinant viruses to the trigeminal ganglion followed by functional assays. We will use intranasal administration to target the trigeminal nerve, which innervates the nasal mucosa. An advantage of this route is that it should deliver virus to the entire trigeminal nerve, including the ophthalmic branch, and connected parts of the CNS while limiting systemic exposure to the viral vector. Combined with the use of a tetracycline regulated promoter system, this approach will allow comparatively localized and acute expression that should minimize compensatory and systemic effects that might occur with a more global transgenic approach. Importantly, the viral approach will also allow us to more readily test different genetic backgrounds, including transgenic mice with additional neuronal CGRP receptor subunits. Aim 1 will establish and optimize the intranasal viral delivery technique and document the expression of bioactive CGRP. Aim 2 will involve a thermal sensitivity assay and two aversive behavioral assays as initial tests for whether overexpressed trigeminal CGRP mimics certain trigeminal pain states. A strength of this proposal is its multidisciplinary approach will involve a team of investigators with expertise in CGRP gene expression, intranasal delivery, nociception, and mouse behavior. In the long term, these studies will potentially provide the foundation for mechanism studies and therapeutic strategies for recalcitrant trigeminal-mediated pathologies such as migraine and temporomandibular diseases. The prevalence and severity of trigeminal pain disorders is a significant health issue. Due to the high incidence and generally poor efficacy of current treatments for migraine and all types of trigeminal pain, there is a need for improved therapeutic and preventative measures. Development of a mouse model for trigeminal mediated pain disorders will potentially provide the foundation for testing the efficacy of drugs and therapeutic gene transfer strategies for recalcitrant trigeminal-mediated pathologies such as migraine.