Fig. 1.
Proposed model for signaling mechanisms involved in aquaporin-2 (AQP-2) regulation in inner medullary collecting duct principal cells. See text for details. A1R, adenosine A1 receptor; AC, adenylyl cyclase; COX-1, cyclooxygenase 1; CREB, cAMP responsive element-binding protein; DAG, diacylglycerol; EP3, PGE2 receptor subtype 3; ET-1, endothelin-1; ETB, endothelin B receptor; Gi, inhibitory G protein; Gq, phospholipase C stimulatory G protein; Gs, stimulatory G protein; IP, inositol triphosphate; βγ, G protein βγ subunit; P, phosphorylation; PKA, protein kinase A; PKC, protein kinase C; PLC, phospholipase C; V2R, vasopressin V2 receptor.