Sex Steroids, and TMJ Pain

描述：本研究的长期目标是确定性别差异和性激素对导致和影响急性和持续性关节疼痛的基因(S)和分子通路的影响，如在颞颌关节及其相关周围组织中所观察到的。这项应用的目的是确定类固醇性激素对急性疼痛的外周效应，并寻找在TMJ模型的疼痛通路中起作用的伤害性感受基因(S)。我们的中心假设是生理雌激素、孕激素和睾酮浓度的变化通过作用于关节和周围关节内和/或三叉神经节内的外周组织(S)来调节TMJ模型中的急性疼痛。为了验证我们的中心假设，并达到这一应用的目标，我们提出了以下两个具体目标：首先，我们将描述女性TMJ及其周围区域与内源性和给予雌激素和黄体酮有关的疼痛。其次，我们将通过确定性类固醇在男性中的调节作用来表征TMJ及其周围区域疼痛的性别差异。具体目标一的工作假设是，女性周期性的血浆雌激素和/或孕酮水平调节TMJ疼痛，部分是通过改变关节和/或三叉神经节的基因表达。为了验证工作假说，实验方法将包括向TMJ上间隙注入完全弗氏佐剂(CFA)。去卵巢的SD大鼠将接受生理剂量的17-β雌二醇和/或黄体酮的治疗，包括激素受体拮抗剂和非激素受体拮抗剂。首先将使用已建立的非侵入性行为程序测试大鼠的TMJ疼痛。这项测试使用吃一顿饭所需的时间(即用餐时间)作为疼痛的行为衡量标准。其次，将用基因芯片测量这些处理动物的TMJ和三叉神经节中近4000个基因转录水平的变化。第三，来自基因阵列研究的候选基因(S)1)受激素治疗调节，2)在疼痛相关通路中的功能将通过实时荧光聚合酶链式反应、酶联免疫吸附试验和/或蛋白质定量来测量转录本和蛋白质水平。具体目标二的工作假设是，男性体内低水平的非周期性血浆雌激素和/或高水平的睾酮通过改变关节和/或三叉神经节的基因表达来调节疼痛。为了验证工作假设，实验方法将包括在TMJ注射CFA之前和之后测量去势和未服用雌激素的雄性大鼠的疼痛(即进餐持续时间)。牺牲后，将测量成绩单水平。我们希望这些数据将用于评估和治疗性别相关的TMJ疾病，并用于激素对关节疼痛作用的机制研究。完成这些拟议研究的基本原理是，一旦确定了影响疼痛敏感性的激素的特征，并确定了关节和三叉神经节中受这些激素效应调控的基因(S)，就可以继续研究TMJ疼痛的药物干预靶点。

DESCRIPTION: The long term goal of this study is to determine the impact of gender differences and sex hormones on gene(s) and molecular pathways leading to and effecting acute and persistent joint pain as observed in the temporomandibular joint (TMJ) and associated peripheral tissues. The objective of this application is to determine the peripheral effect that steroid sex hormones have on acute pain and identify nociception gene(s) that function in pain pathways as modeled in the TMJ. Our central hypothesis is that changes in physiological estrogen, progesterone and testosterone concentrations modulates acute pain as modeled in the TMJ through action at peripheral tissue(s) within and surrounding the joint and/or within the trigeminal ganglia. To test our central hypothesis and attain the objective of this application we propose the following two Specific Aims first, we will characterize pain in the TMJ and surrounding region related to endogenous and administered estrogen and progesterone in females. Second, we will characterize gender differences in pain in the TMJ and surrounding region by determining the modulatory effect of sex steroids in males. The working hypothesis for Specific Aim one is that cyclical plasma levels of estrogen and/or progesterone in females modulates TMJ pain, in part, through changes in gene expression in the joint and/or trigeminal ganglia. To test the working hypothesis the experimental approach will consist of injecting complete Freund's adjuvant (CFA) into the superior TMJ space. The ovariectomized Sprague-Dawley rats will have been treated with physiological doses of 17-beta estradiol and/or progesterone with and without hormone receptor antagonists. The rats will be first tested for TMJ pain using an established non-invasive behavioral procedure. This test uses the time required to eat a meal (i.e., meal duration), as a behavioral measure of pain. Second, changes in the transcript levels of nearly four thousand genes will be measured in the TMJ and trigeminal ganglia of these treated animals with gene microarrays. Third, candidate gene(s) from the gene array studies that were 1) modulated by hormonal treatment and 2) function in pain related pathways will be further quantitated by real-time PCR, ELISA and/or westerns to measure transcript and protein levels. The working hypothesis for Specific Aim two is that low non-cyclical plasma levels of estrogen and/or high testosterone in the males modulates pain through changes in gene expression in the joint and/or trigeminal ganglia. To test the working hypothesis the experimental approach will consist of measuring pain (i.e., meal duration) on castrated and intact male rats treated with and without estrogen before and after injecting CFA in the TMJ. Upon sacrifice transcript levels will be measured. We expect these data will be used for the evaluation and treatment of gender-related TMJ disorders and for mechanistic studies into hormonal action on joint pain. The rationale for completing these proposed studies is that once the hormones influencing pain sensitivity have been characterized and the gene(s) modulated by these hormonal effects in the joint and trigeminal ganglion identified, targets for pharmaceutical intervention of pain in the TMJ can be pursued.