Vasopressin decreases the volume of urine primarily by causing:
In the absence of ADH, collecting ducts are impermeable to water. ADH increases the exocytosis and decreases the endocytosis of water channels (aquaporins) in the collecting duct cells. This results in increase in permeability of collecting ducts to water.
Decrease in glomerular filtration rate
Decrease in renal blood flow
Decrease in water permeability of descending limb of loop of Henle
Increase in water permeability of collecting duct cells
Kidney