DEVELOPMENT OF RECEPTOR-SPECIFIC OPIOID PEPTIDE ANALOGS

我们建议合成有效和稳定的阿片肽类似物， 被设计为i)无MU的高度选择性的三角洲拮抗剂 拮抗剂性质，ii)混合MU激动剂/Delta拮抗剂和iii) 结构刚性的Mu选择性激动剂。待开发的化合物 可能也有助于进一步论证假定的Mu-， β-和kappa-阿片受体亚型及其选择性配体 这样的子类型。高度受体选择性阿片肽激动剂， 在研究中需要拮抗剂或混合激动剂/拮抗剂 特定的阿片类药物效应与不同的受体类别或 亚类以及潜在治疗剂的开发 表现出最小的副作用。为了达到这些目标，我们使用一种 结合多肽合成的跨学科方法， 构象研究和广泛的药理学 人物刻画。多肽类似物的设计将基于各种 原则，包括天然和人造氨基酸的替代， 多肽键取代和构象限制的引入。 具体目标包括：a)合成高度有效和稳定的类似物 三角洲选择性原型拮抗剂H-Tyr-Tic-Phe-Phe-OH(TIPP) 和我们实验室最近发现的H-Tyr-Tic-Phe-OH(TIP)； 基于结构的MU激动剂/三角洲拮抗剂的研究进展 H-Tyr-Tic-Phe-Phe-NH2(TIPP-NH2)或H-Tyr-环[-D-Orn-1- Nal-D-Pro-Gly-]和多肽二聚体的制备；以及c) Mu选择性环状德吗啡肽H-Tyr-的类似物合成 含附加构象的D-Orn-Phe-Asp(或Glu)-NH2 在Tyr1-和/或Phe3-残基或在肽环上的限制 结构；d)分子力学和分子构象研究 动力学技术，以及一维和二维核磁共振波谱 方法；e)测定受体亲和力和选择性 基于Mu~-、Delta~-和Mu~-置换的结合分析新化合物 大鼠或豚鼠脑膜Kappa选择性放射性配基 结合部位；f)评价激动剂和拮抗剂的性质 基于电诱发抑制的生物检测中的类似物 豚鼠回肠和输精管的收缩 小鼠、大鼠和兔子；g)化合物稳定性的检查 抗酶降解；以及h)止痛性能的测试 使用小鼠扭动和热板试验的类似物。

We propose to synthesize potent and stable opioid peptide analogs, designed to be i) highly selective delta antagonists without mu antagonist properties, ii) mixed mu agonists/delta antagonists and iii) structurally rigid mu-selective agonists. The compounds to be developed might also be useful for the further demonstration of putative mu-, delta- and kappa-opioid receptor subtypes and as selective ligands for such subtypes. Highly receptor-selective opioid peptide agonists, antagonists or mixed agonists/antagonists are needed in studies aimed at correlating specific opioid effects with a distinct receptor class or subclass as well as for the development of potential therapeutic agents showing minimal side effects. to reach these goals, we use an interdisciplinary approach incorporating peptide synthesis, conformational investigations and extensive pharmacological characterization. The peptide analog design will be based on various principles, including substitution of natural and artificial amino acids, peptide bond replacements and introduction of conformational constraints. Specific aims include: a) synthesis of highly potent and stable analogs of the delta-selective prototype antagonists H-Tyr-Tic-Phe-Phe-OH (TIPP) and H-Tyr-Tic-Phe-OH (TIP) recently discovered in our laboratory; b) development of mixed mu agonists/delta antagonists based on structural modification of H-Tyr-Tic-Phe-Phe-NH2 (TIPP-NH2) or H-Tyr-cyclo[-D-Orn-1- Nal-D-Pro-Gly-] and on the preparation of peptide dimers; and c) synthesis of analogs of the mu-selective cyclic dermorphin peptide H-Tyr- D-Orn-Phe-Asp(or Glu)-NH2 containing additional conformational constraints at the Tyr1- and/or Phe3- residue or in the peptide ring structure; d) conformational studies by molecular mechanics and molecular dynamics techniques, and by 1- and 2-dimensional NMR spectroscopic methods; e) determination of receptor affinities and selectivities of the new compounds in binding assays based on displacement of mu-, delta- and kappa-selective radioligands from rat or guinea pig brain membrane binding sites; f) evaluation of agonist and antagonist properties of the analogs in bioassays based on inhibition of electrically evoked contractions of the guinea pig ileum and of the vasa deferentia of 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 the mouse writhing and hot plate assays.