The site of action of vasopressin is: (A) Ascending limb of loop of Henle, (B) Descending limb of loop of Henle, (C) Distal tubule, (D) Proximal tubule
Answer is C. Vasopressin (ADH) Increasing the water permeability of distal tubule and collecting duct cells in the kidney, thus allowing water reabsorption and excretion of more concentrated urine. Ref: Ganong's Review of Medical Physiology; 24th edition; page no: 698