Question: are vasopressin and desmopressin the same thing?
Answer: Desmopressin (DDAVP) is a synthetic vasopressin analog, which acts specifically on the V2 receptor (renal tubular cell) responsible for the antidiuretic effect of the hormone. At the dose given, DDAVP has no vasoconstrictor effect because it does not activate the V1 receptor, which is in vascular smooth muscle.