Cloning, functional expression and tissue distribution of human cDNA for the vascular-type vasopressin receptor

We have cloned a human vasopressin receptor from human mesenteric artery using RACE (Rapid Amplification of cDNA Ends) methods. The deduced amino acid sequence of the clone (HV-RACE) encodes a protein of 418 amino acids that showed a strong sequence homology to the previously cloned rat V1A vasopressin receptor. The [3H] arginine vasopressin (AVP) binding to HV-RACE expressed in COS-7 cells was potently inhibited by AVP (Ki = 2.9 nM). Interestingly, a new non-peptide "V1-selective" antagonist OPC-21268 exhibited markedly higher affinity for rat V1A receptor (Ki = 57 nM) rather than for HV-RACE (Ki = 56 microM). With the reverse-transcription polymerase chain reaction assay, we observed a large amount of HV-RACE transcripts in the mesenteric artery, while a small amount in a variety of other tissues. The data show that the clone HV-RACE encodes a human vascular-type vasopressin receptor cDNA.