urotensin ii

Urotensin II (U-II) is an endogenous cyclic peptide composed of 11 amino acids and is recognized as the most potent vasoconstrictor identified to date—more powerful than endothelin-1. Originally isolated from fish spinal cord, U-II has since been found in humans and other mammals. It acts primarily through the G-protein-coupled receptor known as UT (formerly GPR14). U-II and its receptor are widely expressed in various tissues including the cardiovascular system, central nervous system, kidneys, lungs, and endocrine organs. The physiological actions of U-II include strong vascular smooth muscle-dependent vasoconstriction via calcium signaling pathways; however, it can also induce endothelium-dependent vasodilation under certain conditions. Beyond vascular effects, U-II influences cell proliferation (notably vascular smooth muscle cells), cardiac hypertrophy and fibrosis, neuroendocrine activity (stimulating ACTH and epinephrine release), insulin resistance, inflammatory responses (acting as a cytokine), foam cell formation in atherosclerosis development via NADPH oxidase activation and increased oxidative stress. Elevated plasma levels of U-II have been observed in several disease states such as hypertension, heart failure, diabetes mellitus, chronic renal disease/renal failure, pulmonary hypertension/cardiac hypertrophy/atherosclerosis/metabolic syndrome. The UT receptor is being explored as a therapeutic target for cardiorenal diseases[1][3][4][5][8].

Other names

U-IIhU-IIhuman urotensin II