Neural Mechanisms of Gynecological Pain

描述（由申请人提供）：该计划的长期目标是促进对女性慢性盆腔疼痛神经机制的理解。目前的研究集中在子宫内膜异位症，一种由子宫内膜组织的子宫外生长定义的疾病。症状包括生育能力低下和严重的慢性疼痛，包括性交困难（阴道痛觉过敏）、痛经（月经痛）以及其他盆腔和腹部内脏和肌肉疼痛。这些痛苦是出了名的难以减轻。阻碍更好治疗发展的一个主要因素是异位生长和疼痛之间关系的机制知之甚少。存在子宫内膜异位症的大鼠模型（ENDO），其涉及子宫片的腹部动脉上的自体移植。移植形成的囊肿具有与女性异位生长相似的特征。与女性一样，这些大鼠生育能力低下，表现出阴道和腹部肌肉痛觉过敏。拟议的研究将使用该大鼠模型来测试关于ENDO诱导的阴道痛觉过敏的潜在机制的假设。最近的发现，异位生长吸引神经供应，通过spanchnic和迷走神经在大鼠模型中，提供了一个新的方向来研究异位生长和疼痛之间的难以捉摸的关联。目标1中的三项研究将检验以下假设：ENDO诱导的阴道痛觉过敏的发生是由囊肿发育中的神经供应活动产生的中枢神经效应引起的。研究1 - 2将比较以下发育时间过程：（一）囊肿的神经供应（通过用神经元标记物进行免疫染色来可视化），（ii）神经供应中的活性（通过蛋白质外渗评估），（iii）阴道信息的脊髓和脑干处理的变化（通过c-Fos和磷酸化N-甲基-D-天冬氨酸受体NR1 [pNR1]蛋白的神经元表达评估），和（iv）细胞因子的腹膜含量（使用蛋白阵列）。通过从行为学上评估阴道伤害感受，研究3将检验以下预测：如果假设是正确的，在神经活动发展之前去除囊肿应该防止ENDO诱导的痛觉过敏的发展。目标#2中的三项研究将检验以下假设：维持ENDO诱导的阴道痛觉过敏需要通过囊肿的脊髓、脑干、节段间和/或脊髓上效应的神经供应来维持。通过行为学方法，研究1将检验这一假设的预测，即去神经支配的完全发育的囊肿应该减少痛觉过敏。研究2将通过评估完全生长的囊肿的去神经支配如何影响阴道刺激诱导的脊髓和脑干神经元中c-Fos和pNR1表达来不同地检验该假设。研究3将通过评估脊髓横断如何影响脊髓和脑干神经元中阴道刺激诱导的c-Fos和pNR1表达来测试关于节段间和脊髓上效应的假设。研究结果有可能提高对子宫内膜异位症疼痛机制的理解，从而导致新的治疗策略。公共卫生相关性：子宫内膜异位症是育龄期妇女的常见疾病，其中在子宫外发现的子宫组织的异常生长与严重的疼痛有关，这大大降低了生活质量。部分原因是人们对异常生长是如何引起这些疼痛的知之甚少，众所周知，如果不诉诸激素或手术，它们要么产生无法忍受的副作用，要么无法帮助，它们就很难缓解。本申请中提出的研究将使用经验证的啮齿动物模型来研究新发现的发芽以提供异常生长的神经如何影响中枢神经系统过程以诱发疼痛，从而提高知识，从而改善治疗策略。

Description (provided by applicant): The long-term goal of this program is to advance understanding of neural mechanisms of chronic pelvic pain in females. Current studies focus on endometriosis, a disorder defined by extrauteral growths of endometrial tissue. Symptoms include subfertility and severe chronic pains, including dyspareunia (vaginal hyperalgesia), dysmenorrhea (menstrual pain) and other pelvic and abdominal visceral and muscle pains. These pains are notoriously difficult to alleviate. A major factor impeding development of better treatments is that mechanisms underlying the relationship between the ectopic growths and pain are poorly understood. A rat model of endometriosis exists (ENDO) that involves autotransplantion on abdominal arteries of pieces of uterus. The transplants form cysts with characteristics similar to the ectopic growths in women. Like women, the rats are subfertile and exhibit vaginal and abdominal muscle hyperalgesia. The proposed studies will use this rat model to test hypotheses concerning mechanisms underlying ENDO-induced vaginal hyperalgesia. The recent discovery that the ectopic growths attract a nerve supply, via spanchnic and vagus nerves in the rat model, provides a new direction to study the elusive association between the ectopic growths and pain. Three studies in Aim #1 will test the hypothesis that development of ENDO-induced vaginal hyperalge- sia results from central neural effects produced by activity in the cysts' developing nerve supply. Studies 1-2 will compare developmental time courses of: (i) the cysts' nerve supply (visualized by immunostaining with neuronal markers), (ii) activity in the nerve supply (assessed by protein extravasation), (iii) changes in spinal and brainstem processing of vaginal information (assessed by neuronal expression of c-Fos and phosphory- lated N-methyl-D-aspartic acid receptor NR1 [pNR1] proteins), and (iv) peritoneal content of cytokines (using protein arrays). By assessing vaginal nociception behaviorally, Study 3 will test the prediction that, if the hy- pothesis is correct, removing cysts before nerve activity develops should prevent the development of ENDO- induced hyperalgesia. Three studies in Aim #2 will test the hypothesis that maintenance of ENDO-induced vaginal hyperalgesia requires maintenance by the cysts' nerve supply of spinal, brainstem, intersegmental and/or supraspinal effects. With behavioral methods, Study 1 will test the prediction from this hypothesis that denervating fully-grown cysts should reduce the hyperalgesia. Study 2 will test the hypothesis differently, by assessing how denervations of fully-grown cysts affect vaginal-stimulation induced c-Fos and pNR1 express- ion in spinal and brainstem neurons. Study 3 will test hypotheses concerning intersegmental and supraspinal effects by assessing how spinal transections affect vaginal-stimulation-induced c-Fos and pNR1 expression in spinal and brainstem neurons. Results of the studies have the potential for improving understanding of mechanisms that contribute to the pains of endometriosis, thereby leading to new treatment strategies. PUBLIC HEALTH RELEVANCE: Endometriosis is common disorder suffered by women of childbearing age in whom abnormal growths of uterine tissue found outside the uterus are associated with severe pains that greatly reduce quality of life. In part because so little is known about how the abnormal growths give rise to these pains, they are notoriously difficult to alleviate without resorting to hormones or surgery that either produce intolerable side effects or fail to help. Studies proposed in this application will use a validated rodent model to investigate how the newly- discovered nerves that sprout to supply the abnormal growths might influence central nervous system processes to induce the pains, thereby improving knowledge that can lead to improved treatment strategies.