Arginine vasopressin (AVP) is a neuropeptide produced in the hypothalamus. It is involved in many biological processes of both the circulatory system and the central nervous system (CNS), including water homeostasis, renal function, mediation of cardiovascular function, non-opioid mediation of tolerance for pain, regulation of temperature in mammals and modulation of corticotropin release from the pituitary. 1, 2 and 3 AVP acts on three vasopressin ...