title: Systemic plasma levels of nitrite/nitrate (NOx) reflect brachial flow-mediated dilation responses in young men and women.
abstract: 1. The aim of the present study was to determine the relationship between plasma levels of nitrite/nitrite (NO(x)) and brachial flow-mediated dilation (FMD) in healthy young men and women. 2. Brachial artery FMD was assessed non-invasively using high-resolution ultrasound in 36 young men and women (21 +/- 3 years; 18 men and 18 women). Blood samples for NO(x) assays were collected from an indwelling venous catheter in the forearm following an overnight fast and a 36 h low-nitrate diet. 3. Plasma levels of NO(x) were related to peak brachial FMD% (r = 0.53; P = 0.001). The relationship was maintained when the brachial dilation was expressed as absolute diameter change (Deltamm; r = 0.51; P = 0.002) and when it was normalized (/s) to the mean shear rate (r = 0.50; P = 0.002). 4. The present study demonstrates a relationship between peak FMD in the brachial artery and plasma levels of NO(x) in young men and women. This relationship suggests that brachial FMD and/or plasma NO(x) may be used as markers of peripheral endothelial function.
authors.affiliation: Center for Exercise Science, Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, FL 32611, USA. dcasey@hhp.ufl.edu
authors.forename: Darren P
authors.initials: DP
authors.lastname: Casey
authors.forename: Darren T
authors.initials: DT
authors.lastname: Beck
authors.forename: Randy W
authors.initials: RW
authors.lastname: Braith
mesh_terms: D000293:Adolescent; D000328:Adult; D001794:Blood Pressure; D001916:Brachial Artery / Q000502:physiology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D009566:Nitrates / Q000097:blood* / Q000502:physiology; D009573:Nitrites / Q000097:blood*; D012039:Regional Blood Flow; D014664:Vasodilation / Q000502:physiology*
chemical_list: D009566:Nitrates; D009573:Nitrites