STRUCTURE/FUNCTION RELATIONSHIPS OF THE CCK B RECEPTOR

脑内CCK B型受体在脑内发挥重要作用 在调节焦虑和恐慌发作方面。CCK-B受体拮抗剂有 已经被证明可以阻断对CCK的神经元反应，并且已经被提出如下 一种潜在有效的新型抗焦虑药物。隔离 克隆的CCK-B受体并在异种细胞系中表达， 将加快这类新药物的开发。 我们已经分离到编码胃泌素/CCK的第一个克隆成员的cDNA 受体家族，并有证据表明我们的受体与 大脑CCK-B受体。了解结构和结构之间的联系 CCK-B受体的功能将使受体的设计更加合理 对抗者。测定“CCK-B受体”(如 生物胺受体)代表一个相关受体家族，每个受体 有了独特的药理学，而不是单一的受体， 允许开发针对特定受体亚型的药物 大脑。 我们召集了一个由具有以下专长的个人组成的财团 分子生物学、药理学、蛋白质化学和受体 表征承担隔离、表达和 CCK-B和其他相关脑受体的特性。 总的来说，这一组人在建议的所有方面都有经验 项目，并在过去的一年里一直在合作克隆和 胃泌素受体的特征(PNAS，1992，出版中)。 第一个目标是分离CCK-B及其相关受体。 低严格率杂交法和简并PCR检测脑组织 寡核苷酸。CCK-B及其相关受体将被 药理学特征是确定配体结合的特异性和 第二个信使通路与这些受体相连。配基 结合位点将与我们已有的光亲和标记进行映射 以前用来描述这个受体家族的其他成员是 以及一系列新的本征光亲和探针，我们将 专门针对CCK-B受体进行开发。

The cholecystokinin (CCK) type B receptor in brain plays an important role in modulating anxiety and panic attacks. CCK-B receptor antagonists have been shown to block the neuronal response to CCK and have been proposed as a potentially efficacious new class of anti-anxiety medication. Isolation of a cloned CCK-B receptor and expression in a heterologous cell line, would expedite the development of this new class of drugs. We have isolated a cDNA encoding the first cloned member of the gastrin/CCK receptor family and have evidence that our receptor is highly homologous to the brain CCK-B receptor. Understanding the link between structure and function of the CCK-B receptor will allow more rational design of receptor antagonists. Determination of whether the "CCK-B receptor" (like the biogenic amine receptors) represents a family of related receptors, each with characteristic pharmacology, rather than a single receptor, would allow development of drugs targeted to a specific receptor subtype in brain. We have brought together a consortium of individuals with expertise in molecular biology, pharmacology, protein chemistry, and receptor characterization to undertake the isolation, expression, and characterization of the CCK-B and other related brain receptors. Collectively this group is experienced in all aspects of the proposed project and have been working together for the past year on the cloning and characterization of the gastrin receptor (PNAS, 1992, in press). The first objective is to isolate the CCK-B and related receptors from brain by low stringency hybridization and PCR with degenerate oligonucleotides. The CCK-B and related receptors will ten be pharmacologically characterized to determine ligand binding specificity and the second messenger pathways which couple to these receptors. The ligand binding sites will be mapped with photoaffinity labels which we have previously used in characterizing other members of this receptor family as well as with a series of new intrinsic photoaffinity probes which we will develop specifically for the CCK-B receptor.