The Role of the OLAM System in Burn Pain

描述（由申请人提供）：据估计，美国每年发生200万例烧伤，其中约15%的烧伤需要住院治疗。烧伤患者的主要主诉是强烈的，通常是毁灭性的自发性疼痛，伴有持续的机械和热异常性疼痛和痛觉过敏。因此，有一个迫切需要的基础研究，旨在了解烧伤疼痛的机制，并在确定潜在的新的治疗方法，用于治疗it.A的一个突出成员的瞬时受体电位（TRP）配体门控离子通道家族是TRP香草酸亚家族1（TRPV 1）离子通道，并表达在伤害性神经元的一个主要亚群。TRPV 1转导施加于外周组织的各种有害的物理和化学刺激。TRPV 1离子通道在检测许多这些刺激（包括有害热）中起着关键作用，并有助于热痛觉过敏。TRPV 1受体在介导烧伤后疼痛中的作用尚不完全清楚。因此，对TRPV 1导致烧伤后疼痛的机制的进一步研究解决了知识上的一个重要空白，并可能为治疗烧伤后患者提供创新方法。 我们的实验室先前发表的数据揭示了一类新的内源性TRPV 1激动剂，氧化亚油酸代谢物（OLAMs），其在热损伤和炎症组织损伤时释放。最近的初步研究已经确定了细胞色素P450（CYP 450）酶系统介导从暴露于亚油酸的培养神经元中释放OLAM。基于这些研究，以及作为初步数据呈现的其他结果，我们提出热损伤导致持续激活的亚油酸系统，从而产生亚油酸的氧化代谢产物（OLAMs）和TRPV 1的激活。以下具体目标将测试这一创新的假设：具体目标1确定是否热损伤激活辣椒素敏感的伤害感受器通过辣椒素介导的释放的OLAMs。具体目标1使用体外细胞方法来评估外周烧伤后OLAM系统激活TRPV 1的假设。目标1提供了学习膜片钳电生理学的机会，这种方法为我未来的神经生物学家职业生涯提供了一个有价值的工具。具体目标2鉴定热损伤后感觉神经元中上调的β-内酰胺酶。具体目标2将确定和表征烧伤后感觉神经元中上调的β-淀粉样蛋白亚型。这个目标提供了一个很好的机会来学习qRT-PCR和细胞内免疫中和，这两种技术将加强我未来作为神经生物学家的职业生涯。

DESCRIPTION (provided by applicant): It has been estimated that 2 million burn injuries occur yearly in the US, with ~15% of these injuries requiring hospitalization. The primary complaint of burn victims is an intense, often devastating spontaneous pain, with persistence of both mechanical and thermal allodynia and hyperalgesia. Thus, there is a compelling need for fundamental research aimed at understanding mechanisms of burn pain and in identifying potentially novel therapeutic approaches for treating it. A prominent member of the family of transient receptor potential (TRP) ligand-gated ion channels is the TRP vanilloid subfamily 1 (TRPV1) ion channel, and is expressed on a major subpopulation of nociceptive neurons. TRPV1 transduces various noxious physical and chemical stimuli applied to peripheral tissues. The TRPV1 ion channel plays a critical role in detecting many of these stimuli, including noxious heat, and contributes to heat hyperalgesia. The role of the TRPV1 receptor in mediating pain post burn injury is incompletely understood. Thus, further research on the mechanisms by which TRPV1 contributes to post-burn pain addresses an important gap in knowledge and may offer innovative approaches for treating the post-burn patient. Our lab has previously published data revealing a novel class of endogenous TRPV1 agonists, the oxidized linoleic acid metabolites (OLAMs), which are released upon thermal and inflammatory tissue injury. More recent preliminary studies have identified the cytochrome P450 (CYP) enzyme system in mediating the release of OLAMs from cultured neurons exposed to linoleic acid. Based upon these studies, as well as additional results presented as Preliminary Data, we propose that thermal injury leads to persistent activation of a CYP system leading to generation of oxidative metabolites of linoleic acid (OLAMs) and activation of TRPV1. The following specific aims will test this innovative hypothesis: Specific Aim 1 Determine whether thermal injury activates capsaicin-sensitive nociceptors via CYP mediated release of OLAMs. Specific Aim 1 uses in vitro cellular methods to evaluate the hypothesis that the OLAM system activates TRPV1 after peripheral burn injury. Aim 1 affords the opportunity to learn patch clamp electrophysiology, a method providing a valuable tool in my future career as a neurobiologist. Specific Aim 2 Identify CYP enzymes that is up-regulated in sensory neurons after thermal injury. Specific Aim 2 will identify and characterize CYP isoforms that are up-regulated in sensory neurons after burn injury. This Aim provides an excellent opportunity to learn both qRT-PCR as well as intracellular immunoneutralization, two techniques which will strengthen my future career as a neurobiologist.