Skip to main content
main-content

01.12.2012 | Research | Ausgabe 1/2012 Open Access

Cardiovascular Ultrasound 1/2012

Brachial Artery Flow-mediated Dilation Following Exercise with Augmented Oscillatory and Retrograde Shear Rate

Zeitschrift:
Cardiovascular Ultrasound > Ausgabe 1/2012
Autoren:
Blair D Johnson, Kieren J Mather, Sean C Newcomer, Timothy D Mickleborough, Janet P Wallace
Wichtige Hinweise

Electronic supplementary material

The online version of this article (doi:10.​1186/​1476-7120-10-34) contains supplementary material, which is available to authorized users.

Competing interests

The authors declare that they have no competing interests.

Authors’ contributions

BDJ was responsible for conception and study design, data collection, data analysis, statistical analysis and interpretation, and drafting the article. KJM assisted with study design, statistical interpretation, and revised the article for intellectual content. SCN contributed to study design, statistical interpretation, and revised the article for intellectual content. TDM participated in study design, statistical interpretation, and revised the article for intellectual content. JPW contributed to the development of the scientific question, study design, statistical interpretation, and revised the article for intellectual content. All authors read and approved the final manuscript.

Abstract

Background

Acute doses of elevated retrograde shear rate (SR) appear to be detrimental to endothelial function in resting humans. However, retrograde shear increases during moderate intensity exercise which also enhances post-exercise endothelial function. Since SR patterns differ with the modality of exercise, it is important to determine if augmented retrograde SR during exercise influences post-exercise endothelial function. This study tested the hypothesis that (1) increased doses of retrograde SR in the brachial artery during lower body supine cycle ergometer exercise would attenuate post-exercise flow-mediated dilation (FMD) in a dose-dependent manner, and (2) antioxidant vitamin C supplementation would prevent the attenuated post-exercise FMD response.

Methods

Twelve men participated in four randomized exercise sessions (90 W for 20 minutes) on separate days. During three of the sessions, one arm was subjected to increased oscillatory and retrograde SR using three different forearm cuff pressures (20, 40, 60 mmHg) (contralateral arm served as the control) and subjects ingested placebo capsules prior to exercise. A fourth session with 60 mmHg cuff pressure was performed with 1 g of vitamin C ingested prior to the session.

Results

Post-exercise FMD following the placebo conditions were lower in the cuffed arm versus the control arm (arm main effect: P < 0.05) and without differences between cuff pressures (20 mmHg: 5.7 ± 2.2%; 40 mmHg: 4.7 ± 1.3%; 60 mmHg: 5.4 ± 2.4%) (P > 0.05). Following vitamin C treatment, post-exercise FMD in the cuffed and control arm increased from baseline (P < 0.05) but were not different (control: 7.1 ± 3.5% vs. cuffed: 6.6 ± 3.3%) (P > 0.05).

Conclusions

These results indicate that augmented oscillatory and retrograde SR in non-working limbs during lower body exercise attenuates post-exercise FMD without an evident dose–response in the range of cuff pressures evaluated. Vitamin C supplementation prevented the attenuation of FMD following exercise with augmented oscillatory and retrograde SR suggesting that oxidative stress contributes to the adverse effects of oscillatory and retrograde shear during exercise on FMD.
Zusatzmaterial
Authors’ original file for figure 1
12947_2012_432_MOESM1_ESM.tiff
Authors’ original file for figure 2
12947_2012_432_MOESM2_ESM.tiff
Authors’ original file for figure 3
12947_2012_432_MOESM3_ESM.tiff
Authors’ original file for figure 4
12947_2012_432_MOESM4_ESM.tiff
Literatur
Über diesen Artikel

Weitere Artikel der Ausgabe 1/2012

Cardiovascular Ultrasound 1/2012 Zur Ausgabe

Neu im Fachgebiet Innere Medizin

Meistgelesene Bücher aus der Inneren Medizin

2017 | Buch

Rheumatologie aus der Praxis

Entzündliche Gelenkerkrankungen – mit Fallbeispielen

Dieses Fachbuch macht mit den wichtigsten chronisch entzündlichen Gelenk- und Wirbelsäulenerkrankungen vertraut. Anhand von über 40 instruktiven Fallbeispielen werden anschaulich diagnostisches Vorgehen, therapeutisches Ansprechen und der Verlauf …

Herausgeber:
Rudolf Puchner

2016 | Buch

Ambulant erworbene Pneumonie

Was, wann, warum – Dieses Buch bietet differenzierte Diagnostik und Therapie der ambulant erworbenen Pneumonie zur sofortigen sicheren Anwendung. Entsprechend der neuesten Studien und Leitlinien aller wichtigen Fachgesellschaften.

Herausgeber:
Santiago Ewig

Mail Icon II Newsletter

Bestellen Sie unseren kostenlosen Newsletter Update Innere Medizin und bleiben Sie gut informiert – ganz bequem per eMail.

© Springer Medizin 

Bildnachweise