Furthermore, the vasopressin 2 receptor (V2R) signaling pathway involves activation of a stimulatory G protein (Gs) followed by the activation of AC6 and the generation of the secondary messenger cAMP in cyst epithelial cells; accordingly, a V2R blocker is used for ADPKD treatment (9). The gene discussed is AVPR2; the disease is autosomal dominant polycystic kidney disease.