Cardiovascular effects of urocortin 2 and urocortin 3 in patients with chronic heart failure.
Stirrat CG., Venkatasubramanian S., Pawade T., Mitchell AJ., Shah AS., Lang NN., Newby DE.
AIMS: Urocortin 2 and urocortin 3 may play a role in the pathophysiology of heart failure and are emerging therapeutic targets. We aimed to examine the local and systemic cardiovascular effects of urocortin 2 and urocortin 3 in healthy subjects and patients with heart failure. METHODS: Patients with heart failure (n = 8) and age and gender-matched healthy subjects (n = 8) underwent bilateral forearm arterial blood flow measurement using forearm venous occlusion plethysmography during intra-arterial infusions of urocortin 2 (3.6-36 pmol min(-1) ), urocortin 3 (360-3600 pmol min(-1) ) and substance P (2-8 pmol min(-1) ). Heart failure patients (n = 9) and healthy subjects (n = 7) underwent non-invasive impedance cardiography during incremental intravenous infusions of sodium nitroprusside (573-5730 pmol kg(-1) min(-1) ), urocortin 2 (36-360 pmol min(-1) ), urocortin 3 (1.2-12 nmol min(-1) ) and saline placebo. RESULTS: Urocortin 2, urocortin 3 and substance P induced dose-dependent forearm arterial vasodilatation in both groups (P