Research Repository

Effects of nitrate supplementation via beetroot juice on contracting rat skeletal muscle microvascular oxygen pressure dynamics

Ferguson, Scott K, Hirai, Daniel M, Copp, Steven W, Holdsworth, Clark T, Allen, Jason, Jones, Andrew M, Musch, Timothy I and Poole, David C (2013) Effects of nitrate supplementation via beetroot juice on contracting rat skeletal muscle microvascular oxygen pressure dynamics. Respiratory Physiology and Neurobiology, 187 (3). pp. 250-255. ISSN 1569-9048 (print) 1878-1519 (online)

Full text for this resource is not available from the Research Repository.

Abstract

NO3− supplementation via beetroot juice (BR) augments exercising skeletal muscle blood flow subsequent to its reduction to NO2− then NO. We tested the hypothesis that enhanced vascular control following BR would elevate the skeletal muscle O2 delivery/O2 utilization ratio (microvascular PO2, PmvO2) and raise the PmvO2 during the rest-contractions transition. Rats were administered BR (~0.8 mmol/kg/day, n = 10) or water (control, n = 10) for 5 days. PmvO2 was measured during 180 s of electrically induced (1 Hz) twitch spinotrapezius muscle contractions. There were no changes in resting or contracting steady-state PmvO2. However, BR slowed the PmvO2 fall following contractions onset such that time to reach 63% of the initial PmvO2 fall increased (MRT1; control: 16.8 ± 1.9, BR: 24.4 ± 2.7 s, p < 0.05) and there was a slower relative rate of PmvO2 fall (Δ1PmvO2/τ1; control: 1.9 ± 0.3, BR: 1.2 ± 0.2 mmHg/s, p < 0.05). Despite no significant changes in contracting steady state PmvO2, BR supplementation elevated the O2 driving pressure during the crucial rest-contractions transients thereby providing a potential mechanism by which BR supplementation may improve metabolic control.

Item Type: Article
Uncontrolled Keywords: exercise, blood flow, nitrite, nitric oxid
Subjects: FOR Classification > 0606 Physiology
FOR Classification > 1109 Neurosciences
Faculty/School/Research Centre/Department > College of Sports and Exercise Science
Depositing User: Ms Julie Gardner
Date Deposited: 23 Sep 2014 04:59
Last Modified: 23 Sep 2014 06:23
URI: http://vuir.vu.edu.au/id/eprint/25743
DOI: https://doi.org/10.1016/j.resp.2013.04.001
ePrint Statistics: View download statistics for this item
Citations in Scopus: 31 - View on Scopus

Repository staff only

View Item View Item

Search Google Scholar