Development of a Mouse Trigeminal Pain Model

描述（由申请人提供）：研究和治疗三叉神经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，而且往往是神秘的，但许多疾病的共同主题是神经肽CGRP的参与。在这个R21项目中，我提议测试CGRP在小鼠三叉神经节中的过表达会导致行为改变的假设，表明伤害感觉。该方法包括将重组病毒传递到三叉神经节，然后进行功能检测。我们将使用鼻内给药针对三叉神经，它支配鼻黏膜。这种途径的一个优点是，它可以将病毒传递到整个三叉神经，包括眼支和中枢神经系统的连接部分，同时限制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和急性的表达，从而最大限度地减少可能发生的代偿性和系统性影响，而这可能是一个更全面的转基因方法。重要的是，病毒方法也将使我们能够更容易地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将建立和优化鼻内病毒传递技术，并记录生物活性CGRP的表达。目的2将包括热敏试验和两个厌恶行为试验，作为三叉神经CGRP过表达是否模拟某些三叉神经疼痛状态的初步测试。该提案的优势在于其多学科方法将涉及具有CGRP基因表达，鼻内递送，伤害感受和小鼠行为专业知识的研究团队。从长远来看，这些研究将有可能为难治性三叉神经介导的疾病如偏头痛和颞下颌疾病的机制研究和治疗策略提供基础。三叉神经痛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目前的治疗发病率高，一般疗效差，有必要改进治疗和预防措施。三叉神经介导的疼痛疾病小鼠模型的建立，将为测试顽固性三叉神经介导的疾病（如偏头痛）的药物疗效和治疗性基因转移策略提供潜在的基础。

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.