title: Relationship between endogenous concentrations of vasoactive substances and measures of peripheral vasodilator function in patients with coronary artery disease.
abstract: 1. The aim of the present study was to determine the relationship between plasma concentrations of nitrite/nitrate (NO(x)) and endothelin (ET)-1 and non-invasive measures of peripheral vasodilator function in patients with coronary artery disease (CAD). 2. Twenty-two patients with angiographic CAD underwent non-invasive measurement of peripheral vasodilator function in the brachial conduit artery (flow-mediated dilation (FMD) testing via ultrasound) and in the forearm resistance arteries (via venous occlusion plethysmography) during reactive hyperaemia after 5 min ischaemia. In addition, plasma NO(x) and ET-1 concentrations were determined. 3. The plasma concentration of NO(x) was related to the peak brachial FMD response when expressed as either the relative (%) or absolute (mm) change in diameter (r = 0.73, P < 0.001; and r = 0.64, P < 0.01, respectively). Moreover, plasma concentrations of NO(x) demonstrated a relationship with forearm vasodilation estimated by total forearm blood flow following 5 min ischaemia (r = 0.63, P < 0.01) and the flow debt repayment of the forearm (r = 0.54, P < 0.01). Finally, ET-1 concentrations were inversely related to FMD% (r = -0.45, P < 0.05). 4. The findings of the present study demonstrate a relationship between the plasma concentrations of NO(x) and measures of vascular reactivity in conduit and resistance arteries in patients with CAD. Therefore, measurement of plasma NO(x) may serve as a reliable marker for peripheral vasodilator dysfunction in patients with CAD.
authors.affiliation: Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Center for Exercise Science, Gainesville, Florida, USA. casey.darren@mayo.edu
authors.forename: Darren P
authors.initials: DP
authors.lastname: Casey
authors.forename: Wilmer W
authors.initials: WW
authors.lastname: Nichols
authors.forename: C Richard
authors.initials: CR
authors.lastname: Conti
authors.forename: Randy W
authors.initials: RW
authors.lastname: Braith
mesh_terms: D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D003324:Coronary Artery Disease / Q000097:blood* / Q000503:physiopathology*; D019332:Endothelin-1 / Q000097:blood*; D005260:Female; D005542:Forearm / Q000098:blood supply / Q000503:physiopathology; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D017942:Nitric Acid / Q000097:blood; D009569:Nitric Oxide / Q000097:blood; D026361:Reactive Nitrogen Species / Q000097:blood*; D014463:Ultrasonography; D014664:Vasodilation / Q000502:physiology*
chemical_list: D019332:Endothelin-1; D026361:Reactive Nitrogen Species; D009569:Nitric Oxide; D017942:Nitric Acid