Arginine-vasopressin (AVP) modulates the drinking water channel aquaporin-2 (AQP2) in the renal collecting duct to maintain homeostasis of body water. a PKA- and p38-MAPKCdependent pathway. Aquaporin-2 (AQP2) is the water channel mediating arginine-vasopressin (AVP)Cincreases in water re-absorption in renal collecting…