THERAPEUTIC NA+ CHANNEL BLOCKERS: RECEPTOR & DRUG DESIGN

治疗性 NA 通道阻断剂：受体

• 批准号: 6385762
• 负责人: GING K WANG
• 金额: $ 27.54万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6385762
• 关键词: amitriptyline; drug design /synthesis /production; drug metabolism; drug receptors; ion channel blocker; laboratory rat; local anesthetics; receptor binding; sciatic nerve; sheep; site directed mutagenesis; sodium channel; tissue /cell culture; voltage /patch clamp; voltage gated channel

The long term objective of this renewal application is to develop therapeutic Na+ channel blockers pertinent to pain management. Traditional local anesthetics are often unsuited for treatment of chronic or intractable cancer pain because of their insufficient duration of nerve block. There are 4 specific aims: 1. To study the structure-activity relationship of various potent Na+ channel blockers in vitro; 2. To design and synthesize their amphipathic derivatives; 3. To test selected blockers suitable for prolonged nerve block in vivo; and 4. To map their receptor site within the Na+ channel alpha subunit. The first agent to be tested is the tricyclic antidepressant amitryptyline, which is a potent sodium channel blocking agent in addition to its actions at other receptors. With bupivacaine as a standard for comparison, the binding affinities of various tricyclics and other potent sodium channel blockers will be determined in voltage clamp studies on HEK cells transiently transfected with rat skeletal muscle and human heart sodium channel clones; native neuronal sodium channels in rat pituitary GH3 cells will also be used. Elements to be characterized include use-dependence of block and IC50 for resting and inactivated channel block. The working hypothesis for this phase of the studies is that duration of block in vivo will correlate positively with use dependence and negatively with IC50 for inactivated channel states. The in vivo studies will employ behavioral endpoints to examine both sensory and motor nerve block of sciatic nerve following a single injection of each agent in rats; drugs effective in rats will also be tested in the cauda equina space in sheep to model spinal routes of therapy. Drug design and synthesis will initially employ amitryptiline derivatives. Studies of the receptor site in the sodium channel will probe for the locations of two hydrophobic domains using point mutations and studies of drug potency on the mutated channels in HEK cells, with a special emphasis on residues which may be responsible for high-affinity binding of the tricyclic ring. Eventually the studies will be extended to other classes of drugs including phenylacetamides, calcium channel blockers, and a potassium channel blocker that also potently blocks sodium channels. Like tricyclic antidepressants, these agents have multiple phenyl rings but they are separated into two large hydrophobic domains rather than one.

此更新应用的长期目标是开发 与疼痛管理有关的治疗性NA+通道阻滞剂。传统的 局部麻醉通常不适合治疗慢性或棘手 由于神经阻滞持续时间不足，癌症疼痛。有4个 具体目的：1。研究各种的结构活动关系 体外有效的Na+通道阻滞剂； 2。设计和合成他们的 两亲衍生物； 3。测试适合延长的选定阻滞剂 体内神经阻滞；和4。在Na+通道内绘制其受体位点 α亚基。要测试的第一个代理是三环抗抑郁药 Amitryptyline，除了 它在其他受体上的作用。以布比卡因作为比较的标准 各种三轮车和其他有效钠通道的结合亲和力 将在瞬时对HEK细胞的电压夹具研究中确定阻滞剂 用大鼠骨骼肌和人心脏钠通道克隆转染； 还将使用大鼠垂体GH3细胞中的天然神经元钠通道。 要表征的元素包括块的使用依赖性和IC50的使用 休息和灭活的通道块。此阶段的工作假设 研究是，体内块的持续时间将与 使用依赖性并与IC50进行负依赖性，以灭活通道状态。 in 体内研究将采用行为终点来检查感觉和运动 坐骨神经的神经块在单次注射后， 老鼠；在大鼠中有效的药物也将在Cauda Equina空间中进行测试 绵羊为脊柱疗法建模。药物设计和合成将 最初采用阿米替丁衍生物。对受体位点的研究 钠通道将使用使用两个疏水结构域的位置进行探测 HEK突变通道上药物效力的点突变和研究 细胞，特别强调可能导致的残留物 三环环的高亲和力结合。最终研究将是 扩展到其他类别的药物，包括苯乙酰胺，钙通道 阻滞剂和钾通道阻滞剂也有效地阻塞钠 频道。像三环抗抑郁药一样，这些剂具有多种苯基 戒指，但它们分为两个大的疏水域，而不是 一。