DEVELOPMENT OF RECEPTOR-SPECIFIC OPIOID PEPTIDE ANALOGS

我们建议合成有效的、酶抗性的阿片肽类似物 具有对三种主要阿片受体类型（μ，δ， eta）。 开发的化合物也可能用于进一步的 假定的阿片样物质亚型（μ 1，μ 2，η 1，η 2，η 3， eta 4等）和作为这些亚型的选择性配体。 受体- 选择性阿片肽激动剂和拮抗剂需要在研究中， 将特定的阿片类药物作用与不同的受体类别相关联，或 亚类以及用于开发潜在的治疗剂 显示出最小的影响。 为了实现这些目标，我们使用跨学科的 结合肽合成、构象研究的方法 和广泛的药理学特征。 肽类似物设计 将基于各种原则，包括替代天然和 人工氨基酸、肽键置换和引入 构象约束 具体目标包括：a）合成类似物 μ-选择性环状皮吗啡肽Tyr-D-Orn-Phe-Asp-NH 含有构象受限的Tyr和Phe残基， 所述肽序列的位置1（2）和3; B）制备线性和 Deltorphing选择性的环状类似物）; c）合成稳定的 强啡肽A-（1-11）-NH 2类似物表征各种肽键 在1-2位的取代和/或在1- 2位的取代中含有环状元素， 肽链的N-末端区域; d）通过摩尔分析的构象研究 力学和分子动力学技术，并通过一维和二维 e）测定受体亲和力，和 在基于置换的结合测定中新化合物的选择性 来自大鼠或豚鼠脑的μ-、δ-和η-选择性放射性配体 f）评估膜结合位点的激动剂和拮抗剂性质; 基于电诱发抑制的生物测定中的类似物 豚鼠回肠和血管差异的收缩， 小鼠、大鼠和兔; g）化合物的稳定性检查 抗酶降解;和h）测试 用小鼠扭体法和热板法测定类似物。

We propose to synthesize potent, enzyme-resistant opioid peptide analogs with specificity for the three major opioid receptor types (mu, delta, eta). The compound developed might also be useful for the further demonstration of putative opioid subtypes (mu1, mu2, eta1, eta2, eta3, eta4, etc.) and as selective ligands for such subtypes. Receptor- selective opioid peptide agonists and antagonists are needed in studies at correlating specific opioid effects with a distinct receptor class or subclass well as for the development of potential therapeutic agents showing minimal effects. To reach these goals we use an interdisciplinary approach incorporating peptide synthesis, conformational investigations and extensive pharmacologic characterization. The peptide analog design will be based on various principles including substitution of natural and artificial amino acids, peptide bond replacement and introduction of conformational constraints. Specific aims include: a) synthesize analogs of the mu-selective cyclic dermorphin peptide Tyr-D-Orn-Phe-Asp-NH containing conformationally restricted Tyr and Phe residues substituted in positions 1(2) and 3 of the peptide sequence; b) preparation of linear and cyclic analogs of the deltorphing selective); c) synthesis of stable dynorphin A-(1-11)-NH2 analogs characterize various peptide bond replacements in the 1-2 position and/or containing cyclic elements in the N-terminal region of the peptide chain; d) conformational studies by mole mechanics and molecular dynamics techniques, and by 1- and 2-dimensional spectroscopy methods; e) determination of receptor affinities and selectivities of new compounds in binding assays based on displacement of mu-, delta- and eta-selective radioligands from rat or guinea pig brain membrane binding sites; f) evaluation agonist and antagonist properties of the analogs in bioassays based on inhibition electrically evoked contractions of the guinea pig ileum and of the vasa differentials the mouse, rat and rabbit; g) examination of the stability of the compounds against enzymatic degradation; and h) tests of the analgesic properties of the analogs using mouse writhing and hot plate assays.