Trace Amine Receptors in Non Human Primates

描述（由申请人提供）：与充分表征的生物胺不同的痕量胺已知存在于哺乳动物大脑中超过25年。最近发现的哺乳动物痕量胺受体（TAR）家族为探索脑中痕量胺的生理和药理学相关性提供了重要的新资源（Borowsky et al，2001）。与该发现相结合的是意外发现，滥用药物，包括安非他明、MDMA、LSD以及多巴胺，在与药物浓度相关的浓度下刺激大鼠TAR 1介导的cAMP形成（Bunzow et al，2001）。因此，微量胺受体可能直接或间接地有助于精神兴奋剂和致幻药物作用。由于人类和啮齿类动物的微量胺受体在结构、亚型数量和脑分布上存在差异，我们推测非人类灵长类动物将为揭示微量胺亚型的生理和药理学相关性提供更合适的模型。在这方面，初步研究表明，在非人灵长类动物和人类中，TAR 1的序列同一性为96%。为了建立探索TAR亚型功能所需的基础信息，我们将研究非人灵长类TAR亚型的结构、药理学、信号转导和脑分布。目的1：确定在非人灵长类动物中是否存在人TAR亚型（TAR 1、3、4、5）和结构相关的孤儿受体（GPR 57、GPR 58和PNR）。基于这些结果，Aim 2将利用对不同信号转导途径敏感的荧光素酶测定来发现阻断激动剂诱导的受体活化的激动剂以及拮抗剂。为了表征这些受体的药理学特征，将根据荧光素酶试验鉴定的先导化合物开发放射受体试验。目的3利用原位杂交、实时荧光定量RT-PCR和免疫组织化学技术，定位TAR亚型mRNA和蛋白在灵长类动物脑组织中的分布，为进一步研究TAR亚型在脑组织中的表达奠定基础。我们的初步研究表明，灵长类动物的TARs是精神兴奋剂药物滥用的直接靶点。拟议的研究将形成调查的基础上，在灵长类动物模型中的微量胺受体的生理和药理学相关性，并可能提供新的线索，开发治疗药物，以治疗成瘾和可能的神经精神疾病。

DESCRIPTION (provided by applicant): Trace amines, distinguishable from the well-characterized biogenic amines, have been known to exist in mammalian brain for over 25 years. The recent discovery of a family of mammalian trace amine receptors (TARs) presents a significant new resource for exploring the physiological and pharmacological relevance of trace amines in brain (Borowsky et al, 2001). In conjunction with this finding is the unanticipated discovery that drugs of abuse, ranging from amphetamine, MDMA, LSD, as well as dopamine stimulate rat TAR1-mediated cAMP formation at pharmacologically relevant concentrations (Bunzow et al, 2001). Accordingly, trace amine receptors may directly or indirectly contribute to psychostimulant and hallucinogenic drug effects. As human and rodent trace amine receptors diverge in structure, subtype number and brain distribution, we postulate that non-human primates will provide a more suitable model for uncovering the physiological and pharmacological relevance of trace amine subtypes. In this regard, pilot studies indicate a 96% sequence identity for TAR1 in non-human primate and human. To establish fundamental information needed to explore TAR subtype function, we will investigate non-human primate TAR subtype structure, pharmacology, signal transduction and brain distribution. Aim 1 will determine whether human TAR subtypes (TAR1, 3, 4, 5) and structurally related orphan receptors (GPR57, GPR58 and PNR) exist in nonhuman primates. Based on these results, Aim 2 will utilize luciferase assays sensitive to different signal transduction pathways to uncover agonists as well as antagonists that block agonist-induced receptor activation. To characterize the pharmacological profile of these receptors, radioreceptor assays will be developed from lead compound(s) identified from luciferase assays. Aim 3 will map TAR subtype mRNA and protein distribution in primate brain using in situ hybridization, real-time RT-PCR and immunohistochemistry, to discern which receptor subtypes are expressed in brain for further exploration. Our pilot studies suggest that primate TARs are direct targets of psychostimulant drugs of abuse in brain. The proposed studies will form the basis for investigating the physiological and pharmacological relevance of trace amine receptors in a primate model, and may provide novel leads for developing therapeutic agents to treat addiction and possibly neuropsychiatric disorders.