Urotensin II

Urotensin II (UII) is a cyclic peptide initially isolated from the urophysis of the goby fish (Gillichthys mirabilis) on the basis of its potent vasoconstrictor effect. UII has a cyclic structure of 6 aa residues flanked by two Cys residues, which is fully conserved. UII is present in all vertebrate species from lampreys to mammals. A UII paralog called UII-related peptide (URP) also exists in tetrapods and teleosts. UII induces vasoconstriction, proliferation of vascular smooth muscle cells, multiple behavioral effects (hyperlocomotion, anxiogenic and depressant effects, orexigenic and dipsigenic effects), osmoregulation, and immune response through the UII receptor (UTR) in mammals and teleosts. Recent studies show tthat UII is associated with cardiovascular diseases, atherosclerosis, diabetes, renal dysfunction, hypertension, and obesity. UII is thought to play a central role in the pathogenesis of the metabolic syndrome.