Morel A, Lolait S J, Brownstein M J
Département de Biologie Cellulaire et Moléculaire, Centre d'Etudes de Saclay, Gif sur Yvette, France.
Regul Pept. 1993 Apr 29;45(1-2):53-9. doi: 10.1016/0167-0115(93)90182-8.
Vasopressin, one of the first characterized neuropeptides, has a wide spectrum of biological action, acting on distinct tissues. Indeed, it is involved in water retention, glucose metabolism, blood pressure and its implication in the CNS has also been described. This diversity of effects on mammalian tissues is mediated by distinct G protein-coupled receptors, acting via distinct second messenger pathways. This receptor family has been subtyped by pharmacological studies, as V1a receptor whose action is mediated by intracellular calcium mobilization, and V2 receptor which is linked to adenylyl cyclase. Since so many essential functions were ensured by vasopressin, molecular characterization of its receptors became soon a great challenge. This prompted us to isolate the cDNA of AVP V1a receptor as the first member of this family, by expression cloning. Intracellular calcium mobilization was therefore assayed after rat liver mRNA injection into Xenopus oocytes. A single clone, encoding a functional AVP receptor corresponding to the V1a subtype was finally characterized as a G protein-coupled receptor. Furthermore, we used homology cloning strategy in order to clone the AVP V2 subtype from a rat kidney cDNA library. A putative receptor clone was finally characterized as the rat V2 receptor cDNA by binding and cAMP increase experiments, on transfected cells.
血管加压素是最早被鉴定的神经肽之一，具有广泛的生物学作用，作用于不同的组织。实际上，它参与水潴留、葡萄糖代谢、血压调节，其在中枢神经系统中的作用也已被描述。血管加压素对哺乳动物组织的这种多样作用是由不同的G蛋白偶联受体介导的，通过不同的第二信使途径发挥作用。通过药理学研究，这个受体家族已被分为不同亚型，如作用由细胞内钙动员介导的V1a受体，以及与腺苷酸环化酶相关的V2受体。由于血管加压素确保了如此多的重要功能，其受体的分子特征很快就成为了一个巨大的挑战。这促使我们通过表达克隆分离出AVP V1a受体的cDNA，作为该家族的第一个成员。因此，在将大鼠肝脏mRNA注射到非洲爪蟾卵母细胞后，检测细胞内钙动员情况。最终鉴定出一个编码与V1a亚型相对应的功能性AVP受体的单一克隆，它是一种G蛋白偶联受体。此外，我们使用同源克隆策略，从大鼠肾脏cDNA文库中克隆AVP V2亚型。通过对转染细胞进行结合和cAMP增加实验，最终将一个推定的受体克隆鉴定为大鼠V2受体cDNA。
