Vasopressin is a cyclic nonapeptide endocrine hormone synthesized as a prohormone in the hypothalamus and secreted to the circulation from the posterior pituitary. Its alternate name, anti-diuretic hormone (ADH), describes its best-known function. When receptors in the hypothalamus sense high osmolarity or low volume in the blood, vasopressin is released. Upon hormone binding to V2 receptors in the kidney collecting ducts, aquaporin water channels move to the cell membrane and allow water to be reabsorbed. This molecule is named vasopressin because it binds to V1a receptors in the vasculature to cause smooth muscle contraction. A third type of vasopressin receptor, V1b, occurs in brain tissue and is involved with the secretion of ACTH in response to stress and other neurological responses. We offer specific agonists and antagonists to the three receptors, enabling the researcher to study the vasopressin effect of interest. In addition, copeptin, the carboxyl-terminal fragment of the prohormone, serves as a diagnostic marker for several diseases such as sepsis because of its stability relative to vasopressin. We list both Arg-vasopressin, the form found in humans and most mammals, as well as Lys-vasopressin, found in pigs and marsupials.
Copeptin, the C-terminal part of the vasopressin prohormone is a stable and sensitive surrogate marker for AVP release. Copeptin, a 39-amino acid glycopeptide that comprises the C-terminal part of the Arginine vasopressin (AVP) precursor (CT-proAVP), is cosynthesized with AVP. AVP is a primary secretagogue of the hypothalamo–pituitary–adrenal axis, a key hormone for maintaining fluid balance and vascular tone, and is a marker of acute endogenous stress. However, it has a short half-life and measurement of mature AVP is difficult and subject to errors. Copeptin in contrast is stable and easily measured.
Endogenous antidiuretic hormone in most mammalian species. It is released into the blood from nerve terminals in the posterior pituitary and median eminence. Arg8-vasopressin is also a neurotransmitter in the central nervous system. It is implicated in a variety of physiological processes including diuresis, vasoregulation, and memory. Regulates water balance by antidiuretic action; contracts arterioles (vasopressor action).
Endogenous antidiuretic hormone in most mammalian species. It is released into the blood from nerve terminals in the posterior pituitary and median eminence. Arg8-vasopressin is also a neurotransmitter in the central nervous system. It is implicated in a variety of physiological processes including diuresis, vasoregulation, and memory. Regulates water balance by antidiuretic action; contracts arterioles (vasopressor action).
