CHARACTERIZATION OF NOVEL NEUROACTIVE COMPOUNDS FROM CNIDARIA VENOMS

刺胞动物毒液中新型神经活​​性化合物的表征

• 批准号: 6668376
• 负责人: ANGEL ANNE YANAGIHARA
• 金额: $ 24.81万
• 依托单位: UNIVERSITY OF HAWAII AT MANOA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6668376
• 关键词: Cnidaria; Xenopus; Xenopus oocyte; animal extract; calcium channel blockers; calcium indicator; cooperative study; crayfish; drug discovery /isolation; electrophysiology; marine toxins; neuroprotectants

Venoms have historically proven to be a rich source of powerful neuroactive agents. Recent discovery of SNX-325, a selective blocker of class B (N-type) calcium channels, has provided clinicians with a novel agent for the treatment of intractable pain. Currently available calcium channel drugs, including the dihydropyridines, target channels are functionally and pharmacologically distinct from the peripheral L-type channels and the exploration of their therapeutic modulation is limited by the present lack of specific agonists and antagonists. Drugs targeted toward these channels would be useful, for example, in minimizing neuronal damage caused by excess calcium entry during periods of ischemia. Recent findings from the applicant's laboratory demonstrate that the most powerful of the Hawaiian water coelenterate venoms, Carybdea alata venom, contains at least three distinct activities. The general goal of the collaborative research proposed is to augment the ability of the applicant to screen for novel neuroactive agents using ion flux measurements utilizing imaging techniques for various ions including Ca2+ and Na+. Potential identification of novel calcium channel blockers may ultimately result in elucidation of therapeutic interventions to accomplish neuroprotection which may be applied in the treatment of ischemia and other types of brain injury. Studies are proposed to test the working hypothesis that this venom, as well as other blockers. To test this, the effects of isolated constituent toxins will be tested on various model preparations including crayfish nerve chord (electrophysiological measurement) and single neuronal cells (ion flux and cAMP measurements utilizing fluorescence imaging techniques). The project will be conducted as an integrated and coordinated collaboration between investigators at the University of Hawaii and Johns Hopkins University. The applicant's component of the project will focus on biochemical separation of unique constituent toxins and their respective electrophysiological and morphological effects upon target tissues, while the collaborating component will focus on the evaluation of ion flux and secondary messenger system effects, with particular emphasis on calcium and cAMP flux measurements. The hypotheses to be tested in both components are closely interrelated as are the experimental designs, and will allow the complementary expertise of the investigators to be applied in a maximally productive and mutually beneficial way. The collaboration will also provide ample opportunities for students and fellows at the University of Hawaii to obtain training in the basic neuroscientific techniques to be implemented in the conduct of this research effort.

历史证明，毒液是强大的神经活性剂的丰富来源。最近发现的 B 类（N 型）钙通道选择性阻断剂 SNX-325 为临床医生提供了一种治疗顽固性疼痛的新药。目前可用的钙通道药物，包括二氢吡啶，靶通道在功能和药理学上与外周L型通道不同，并且由于目前缺乏特异性激动剂和拮抗剂，对其治疗调节的探索受到限制。针对这些通道的药物将很有用，例如，可以最大限度地减少缺血期间过量钙进入引起的神经元损伤。申请人实验室的最新研究结果表明，夏威夷水腔肠动物毒液中最强大的毒液——Carybdea alata 毒液至少包含三种不同的活性。所提出的合作研究的总体目标是增强申请人利用包括Ca2+和Na+在内的各种离子的成像技术进行离子通量测量来筛选新型神经活​​性剂的能力。新型钙通道阻滞剂的潜在鉴定可能最终导致阐明实现神经保护的治疗干预措施，其可应用于治疗缺血和其他类型的脑损伤。提议进行研究来检验这种毒液以及其他阻断剂的工作假设。为了测试这一点，将在各种模型制剂上测试分离的成分毒素的影响，包括小龙虾神经索（电生理测量）和单个神经元细胞（利用荧光成像技术的离子通量和 cAMP 测量）。该项目将作为夏威夷大学和约翰霍普金斯大学研究人员之间综合协调的合作进行。该项目申请人的部分将重点关注独特成分毒素的生化分离及其各自对目标组织的电生理和形态学影响，而合作部分将重点评估离子通量和次级信使系统的影响，特别强调钙和cAMP 通量测量。在这两个部分中要测试的假设与实验设计一样密切相关，并且将使研究人员的互补专业知识能够以最大成效和互惠互利的方式应用。此次合作还将为夏威夷大学的学生和研究员提供充足的机会，让他们获得在这项研究工作中实施的基本神经科学技术的培训。