Vasopressin: abbr. VP. This protein is called also Antidiuretic hormone
(ADH), Adiuretin, Vasotocin, Pituitrin P and Pitressin. It is a cyclic
nonapeptide (1,6 disulfide bridge) synthesized in the hypothalamus and stored in
the posterior lobe of the pituitary from which it is released into the
circulation as necessary. AVP has been found also in other tissues, including
testis, ovary, uterus, adrenal gland, superior cervical ganglion, and thymus
(Clements and Funder, 1986). The term Arginine vasopressin (Arg-Vasopressin,
abbr. AVP or ARVP) refers to the presence of an arginine residue at position 8
(which can be occupied also by lysine (Lysine vasopressin, abbr. LVP); residues
3 and 4 have been shown also to be variable. Desmopressin
(1-Desamino-8-D-Arginine vasopressin; abbr. DDAVP) is a synthetic analog of
arginine vasopressin that is well tolerated after systemic administration.
The human vasopressin gene encodes a larger protein product (termed
AVP-NpII, arginine-vasopressin-neurophysin II, vasopressin-neurophysin
2-copeptin) (Sausville et al, 1985). Vasopressin is derived from exon 1 of the
gene. A protein designated neurophysin or neurophysin-2 (exon 2) functions as a
carrier protein (Brownstein et al, 1980). A third glycoprotein, termed copeptin,
is encoded by exon 3 (Land et al, 1982; Ivell and Burbach, 1991). Mutations in
the Vasopressin gene have been found in rats with hereditary diabetes insipidus
(Brattleboro rats). These animals are deficient in synthesis of both arginine
vasopressin and one species of neurophysin (Sunde and Sokol, 1975; Schmale et
al, 1984). Mutations have been found also in human patients with familial
autosomal dominant neurohypophyseal diabetes insipidus (Ito et al, 1997; Rittig
et al, 1996). Ito et al (1997) have suggested that the cellular toxicity in
familial neurohypophyseal diabetes insipidus may be caused by the intracellular
accumulation of mutant precursor
proteins. (http://www.copewithcytokines.de/)
Desmopressin (1-Desamino-8-D-Arginine vasopressin; abbr. DDAVP) is a
synthetic analog of arginine vasopressin. Among other things, this compound
increases the expression of factor VIII and von Willebrand factor in healthy
individuals, but, unlike natural vasopressin, it has little or no effect on
vasoconstriction, does not increase blood pressure, and has no effect on the
contraction of the uterus or gastrointestinal tract (Cash et al, 1974; Mannucci
et al, 1975) (http://www.copewithcytokines.de/)
Nasal desmopressin is used to control the symptoms of a certain type of diabetes
insipidus ('water diabetes'; condition in which the body produces an abnormally
large amount of urine). Nasal desmopressin is also used to control excessive
thirst and the passage of an abnormally large amount of urine that may occur
after a head injury or after certain types of surgery. One brand of desmopressin
nasal spray (Stimate®) is used to stop bleeding in people who have
certain bleeding disorders. Desmopressin is in a class of medications called
hormones. It works by replacing vasopressin, a hormone that is normally produced
in the body to help balance the amount of water and salt.(http://www.nlm.nih.gov/)
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