Vasopressin receptors

The biological effects of arginine vasopressin (AVP) are mediated by three receptor subtypes: the V-1a and V-1b receptors that activate phospholipases via G(q/11), and the V-2 receptor that activates adenylyl cyclase by interacting with Gs. Isolation of the cDNAs encoding the V-1a and V-1b receptor subtypes explained the tissue variability of V-1 antagonist binding, whereas identification of the cDNA and gene encoding the V-2 receptor provided the information to identify the mutations responsible for X-linked nephrogenic diabetes insipidus. Mutations that abrogate the production and/or release of AVP from the pituitary have diabetes insipidus as their most dramatic manifestation, indicating that the maintenance of water homeostasis is the most important physiological role of this neuropeptide. Evidence for a significant role of AVP in blood pressure control, although actively sought, has been scant.