Urotensin-II levels in acute coronary syndromes

Background Urotensin-II (U-II) is a vasoactive peptide with diffuse expression in human cardiomyocyte and vascular smooth muscle cells. Recent studies have reported increased plasma levels of U-II in patients with congestive heart failure. Objective We sought to determine the plasma levels of U-II in patients with acute coronary syndromes (ACS), stable coronary artery disease (CAD) and healthy controls. Methods We prospectively measured plasma U-II levels in 54 patients with ACS, 51 patients with stable coronary disease and 29 healthy volunteers. Monoclonal antibodies against U-II were generated and plasma U-II levels were determined by radioimmunoassay from extracted venous samples. Results ACS patients had significantly lower levels than patients with stable CAD and healthy controls (2.53 ± 1.62 vs. 3.45 ± 2.53 vs. 3.3 ± 3.9 ng/ml, p = 0.008, respectively). In both ACS and stable CAD patients, we found a negative relationship between plasma U-II levels and systemic arterial pressures. The correlation coefficients for systolic and mean arterial pressure were −0.272, p = 0.006 and −0.209, p = 0.04, respectively. Conclusions Plasma U-II levels were significantly decreased in patients with acute coronary syndromes and related negatively to systemic arterial pressures. This finding suggests a down-regulation of U-II expression in patients with acute coronary syndromes. Condensed abstract Urotensin-II (U-II) is a vasoactive peptide with diffuse staining in human cardiomyocytes and vascular smooth muscle cells. We measured plasma U-II levels in patients with acute coronary syndromes (ACS), stable coronary artery disease (CAD) and healthy controls. We observed lower U-II levels in ACS patients and a negative correlation between U-II levels and systemic arterial pressure. This finding suggests a down-regulation of U-II expression in patients with ACS.