Comparison of two competitive enzyme immunoassay kits for quantification of plasma Urotensin-II in rats.

Changes in Urotensin-II (U-II) concentration, a potent vasoconstrictor peptide, have been detected in various pathologies, but it has been impossible to define a normality range. We aimed to analyze the concordance and interchangeability between two enzyme immunoassay methods developed by Phoenix Pharmaceuticals, Inc. to measure U-II plasma concentration in rats: ELISA and fluorescent EIA.