Increased circulating urotensin II in cirrhosis: Potential implications in liver disease

Urotensin II (UII) is a potent vasoactive mediator which, through interaction with a specific G-protein coupled receptor, can result in either a vasoconstrictive or vasodilatory response. In addition to its effect upon vascular tone, UII possess mitogenic and fibrogenic potential. The influence of UII on vascular tone is to some degree both species-specific and disease-specific. Increased circulating UII levels have been documented in subjects with liver cirrhosis although the significance of this finding with regards to the development of chronic liver disease and portal hypertension has yet to be fully elucidated. In this review we focus on the potential relevance of UII as a vasoactive mediator in the chronic liver disease population and postulate as to the site of overproduction of UII.