Constrictory activity of three new arginine-vasopressin (AVP) analogues (ALA-AVP, SER-ALA-AVP, THR-SER-ALA-AVP) towards isolated rat tail artery as related to AVP alone

Summary The constrictory activity of vasopressin and its three novel analogues extended by 1–3 amino acids in accordance with the sequence of the bovine arginine-vasopressin neurophysin II precursor has been studied on isolated rat tail artery preparation. The analogues showed lower constrictory potency than AVP, but these agents strongly interacted with AVP. The net effect of interactions appeared complex and dependent on the nature and concentrations of the interacting agents.