Arginine vasopressin . See

Peptide-secreting cells of the hypothalamic-hypophyseal circuits originally were described as neurosecretory cells, receiving synaptic information from other central neurons, yet secreting transmitters in a hormone-like fashion into the circulation. The transmitter released from such neurons was termed a neurohormone, i.e., a substance secreted into the blood by a neuron. These hypothalamic neurons also may form traditional synapses with central neurons, and cytochemi-cal evidence indicates that the same substances that are secreted as hormones from the posterior pituitary (oxytocin, arginine-vasopressin see Chapters 29 and 55) mediate transmission at these sites. Thus, the designation hormone relates to the release at the posterior pituitary and does not necessarily describe all actions of the peptide. 

The principal hormones of the human posterior pituitary include the two nonapeptides, oxytocin [50-56-6] and arginine vasopressin [11000-17-2] (antidiuretic hormone, ADH). Many other hormones, including opioid peptides (see Opioids, endogenous), cholecystokinin [9011-97-6] (CCK) (see Hormones, BRAIN oligopeptides), and gastrointestinal peptides, also have been located in mammalian neurohypophysis (6), but are usually found in much lower concentrations (7). Studies have demonstrated that oxytocin and vasopressin are synthesized in other human organs, both centrally and peripherally, and there is considerable evidence for their role as neurotransmitters (see Neuroregulators) (8). 

Desmopressin acetate (arginine vasopressin) increases the factor VIII activity of patients with mild hemophilia A or von Willebrand disease. It can be used in preparation for minor surgery such as tooth extraction without any requirement for infusion of clotting factors if the patient has a documented adequate response. High-dose intranasal desmopressin (see Chapter 17 Vasoactive Peptides) is available and has been shown to be efficacious and well tolerated by patients. 

For [8-Arg]-vasopressin, see Meienhofer J, Trzeciak A, Havran RT, Walter R. Solid-phase synthesis of [8-arginine]-vasopressin through a crystalline protected nonapeptide intermediate and biological properties of the hormone. J. Am. Chem. Soc. 1970 92 7199-7202. 

The posterior pituitary gland, also known as the neurohypophysis, contains the endings of nerve axons arising from distinct populations of neurons in the supraoptic and paraventricular nuclei that synthesize either arginine vasopressin or oxytocin. Arginine vasopressin plays an important role in water homeostasis (see Chapter 29) oxytocin plays important roles in labor and parturition and in... 

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