Urotensin II in end-stage renal disease: an inverse correlate of sympathetic function and cardiac natriuretic peptides.

BACKGROUND

Urotensin II (UTN) is a peptide highly conserved across species with disparate effects on the vascular system and it is currently unclear whether high plasma UTN levels play a vasculotoxic or a vasculoprotective role.

METHODS

In this study, we investigated the relationship between plasma UTN and sympathetic activity and cardiac natriuretic hormones in 191 hemodialysis (HD) patients without clinical evidence of heart failure.

RESULTS

Plasma UTN was significantly higher in patients with end-stage renal disease (ESRD) (median: 6.5 ng/mL) than in age matched healthy subjects (median: 3.1 ng/mL) (p<0.001). On univariate analysis, UTN was inversely related to heart rate (r=-0.24), dialysis treatment duration (r=-0.27), norepinephrine (r=-0.28), neuropeptide Y (NPY) (r=-0.66), brain natriuretic peptide (BNP) (r=-0.41) and atrial natriuretic peptide (ANP) (r=-0.28) (all p<0.008). Of note, in multiple regression analyses these associations maintained strength similar to that of the corresponding unadjusted correlation coefficients.

CONCLUSIONS

The inverse links between UTN and neuro-hormonal factors indicate that UTN down-regulation in the presence of high sympathetic activity and high BNP could be a counter-regulatory response aimed at mitigating cardiovascular (CV) damage or that UTN itself acts as a protective factor.