Antidiuretic response in conscious dogs following peroral administration of arginine vasopressin and its analogues.

Conscious dogs were subjected to a constant water load causing water diuresis. When arginine vasopressin or analogues of vasopressin were administered through a gastric tube a dose-dependent antidiuretic response occurred. All the peptides tested proved to be antidiuretic in doses of 50 micrograms or less with 1-deamino-8-D-arginine vasopressin and 1-deamino-4-asparagine-8-D-arginine vasopressin being the most potent substances. No pressor response was observed even after 1 mg of AVP.