Structural and Funtional Characterization of Bradykinin Receptors in Teleost Fish

硬骨鱼缓激肽受体的结构和功能特征

• 批准号: 9806997
• 负责人: J. Michael Conlon
• 金额: $ 17.29万
• 依托单位: Creighton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 2001-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9806997&HistoricalAwards=false
• 关键词: Structural; Funtional; Characterization; Bradykinin; Receptors

9806997 Conlon The effects of brandykinin (BK) in mammals are mediated through interaction with discrete receptors, termed B1 and B2. Activation of the kallikrein-kinin system in the teleost fish, rainbow trout and Atlantic cod generates (Arg0,Trp5,Leu8)-BK (trout/cod BK). The effects of this peptide on the motility of gastrointestinal smooth muscle and on blood pressure in these species are mediated via receptors that are pharmacologically different from each other and from mammalian B1 and B2 receptors. It is proposed to gain insight into BK receptor evolution by cloning BK receptors from a trout intestinal cDNA library and a cod genomic library and characterizing them structurally. Structure-activity relationships of trout/cod BK will be investigated by synthesizing analogs in which each amino acid residue in the peptide has been systematically replaced either by alanine or by its D-isomer. The effect of the substitutions on (a) receptor-binding properties using cultured mammalian cells that have been transiently transfected with the cloned trout and cod BK receptors, (b) elevation of arterial blood pressure in the unanesthetized cod, and (c) motility of trout stomach and cod intestine will be determined. Antagonists to the trout and cod BK receptors will be developed and their properties evaluated in these bioassays. The effect of trout/cod BK on gastric acid and pepsinogen secretion by isolated mucosa from trout stomach, electrolyte transport in the isolated trout intestine and on urine production by the trout kidney will be studied. Taken together, the data will provide insight into the properties of "ancestral" BK receptor from which the mammalian receptors may have evolved and will lead to a greater understanding of the physiological role of the kallikrein-kinin system in teleost fish.

9806997 Conlon 布兰迪激肽 (BK) 在哺乳动物中的作用是通过与离散受体（称为 B1 和 B2）的相互作用介导的。 硬骨鱼、虹鳟鱼和大西洋鳕鱼中激肽释放酶-激肽系统的激活会生成 (Arg0,Trp5,Leu8)-BK (鳟鱼/鳕鱼 BK)。 在这些物种中，该肽对胃肠道平滑肌运动和血压的影响是通过药理学上彼此不同以及与哺乳动物 B1 和 B2 受体不同的受体介导的。 建议通过从鳟鱼肠 cDNA 文库和鳕鱼基因组文库中克隆 BK 受体并对其进行结构表征来深入了解 BK 受体的进化。 将通过合成类似物来研究鳟鱼/鳕鱼 BK 的结构-活性关系，其中肽中的每个氨基酸残基已系统地被丙氨酸或其 D 异构体取代。 将确定这些取代对以下方面的影响：(a) 使用已被克隆的鳟鱼和鳕鱼 BK 受体瞬时转染的培养哺乳动物细胞的受体结合特性；(b) 未麻醉的鳕鱼中动脉血压的升高；以及 (c) 鳟鱼胃和鳕鱼肠的运动性。 将开发鳟鱼和鳕鱼 BK 受体的拮抗剂，并在这些生物测定中评估其特性。 将研究鳟鱼/鳕鱼 BK 对离体鳟鱼胃粘膜分泌的胃酸和胃蛋白酶原、离体鳟鱼肠中电解质运输以及对鳟鱼肾产生尿液的影响。 总而言之，这些数据将提供对“祖先”BK 受体特性的深入了解，哺乳动物受体可能是从该受体进化而来的，并将有助于更好地了解激肽释放酶-激肽系统在硬骨鱼中的生理作用。