Dietary nitrate supplementation augments nitric oxide synthase-dependent and independent reflex cutaneous vasodilation in healthy humans
Year: 2013
Type: dissertation
Abstract: Beetroot juice (BRJ) has been shown to increase NO-dependent dilation through both NOS-dependent and NOS-independent pathways.We hypothesized BRJ supplementation would augment reflex cutaneous active vasodilation.Subjects were equipped with two microdialysis fibers on the forearm and randomly assigned as control (Ringer's) or NOS inhibition (20mM L-NAME).Whole-body heating was achieved via water-perfused suits to raise core temperature (Tc; ingestible telemetric pill) 0.8°C.Maximal cutaneous vasodilation was reached by administering 54mM SNP and local heating to 43°C.Skin blood flow was measured via laser-Doppler flowmetry and mean arterial pressure determined; cutaneous vascular conductance (CVC) was calculated and expressed as %CVC max .Subjects underwent heat stress pre-and postnitrate supplementation (3 days of BRJ: 5mM, 0.45g nitrates per day).BRJ increased the plateau CVC at control (pre: 57 ± 3 vs.post: 80 ± 5 %CVC max ) and L-NAME (pre: 36 ± 3 vs.post: 52 ± 6 %CVC max ; p<0.05 for all conditions) sites.The %NO contribution increased from pre-to post-BRJ (pre: 44 ± 5 %CVC max vs. post: 64 ± 6 %CVC max ; p<0.05).These data suggest that BRJ augments the NOS-dependent and NOS-independent component of reflex cutaneous vasodilation.Chapter 1 -Introduction .......................
Author: Levitt, Erica L.
Language: English
Subfield: Physiology (medical)
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2259422793