scholarly journals Exercise intensity modulates brachial artery retrograde blood flow and shear rate during leg cycling in hypoxia

2015 ◽  
Vol 3 (6) ◽  
pp. e12423 ◽  
Author(s):  
Erika Iwamoto ◽  
Keisho Katayama ◽  
Koji Ishida
Pulse ◽  
2021 ◽  
pp. 1-10
Author(s):  
Smriti Badhwar ◽  
Dinu S. Chandran ◽  
Ashok K. Jaryal ◽  
Rajiv Narang ◽  
Chetan Patel ◽  
...  

<b><i>Introduction:</i></b> The relationship between low flow-mediated constriction (LFMC), a new proposed measure of endothelial function, with cardiovascular disease severity and its hypothesized stimulus, that is, low flow, has not been comprehensively evaluated. The study evaluated association between change in brachial artery diameter during constriction with severity of myocardial perfusion defect (PD) and alterations in different components of flow profile. <b><i>Methods:</i></b> Brachial artery responses to occlusion were assessed in 91 patients and 30 healthy subjects. Change in anterograde and retrograde blood flow velocities (delta anterograde blood flow velocity and retrograde blood flow velocity), anterograde shear rate and retrograde shear rate (delta ASR and RSR, respectively), and oscillatory shear index (delta) during forearm occlusion at 50 mm Hg above systolic pressure, from baseline was calculated. Myocardial perfusion was evaluated in patients using exercise single positron emission computed tomography and % myocardial PD was calculated from summed stress score. <b><i>Results:</i></b> LFMC emerged as independent predictor of defect severity after correcting for age and gender (<i>p</i> = 0.014). Sixty-seven patients (73.6%) and 15 healthy subjects (50%) showed constriction during occlusion. In stepwise backward regression analysis, RSR contributed 35.5% and ASR contributed 20.1% of the total 63.9% variability in artery diameter during occlusion. <b><i>Conclusion:</i></b> The results suggest that LFMC is independently associated with myocardial perfusion severity and is “mediated” by an altered flow profile during occlusion.


2014 ◽  
Vol 46 ◽  
pp. 746
Author(s):  
Erika Iwamoto ◽  
Keisho Katayama ◽  
Shin Yamashita ◽  
Koji Ishida

2011 ◽  
Vol 110 (2) ◽  
pp. 389-397 ◽  
Author(s):  
Grant H. Simmons ◽  
Jaume Padilla ◽  
Colin N. Young ◽  
Brett J. Wong ◽  
James A. Lang ◽  
...  

Acute leg exercise increases brachial artery retrograde shear rate (SR), while chronic exercise improves vasomotor function. These combined observations are perplexing given the proatherogenic impacts of retrograde shear stress on the vascular endothelium and may be the result of brief protocols used to study acute exercise responses. Therefore, we hypothesized that brachial artery retrograde SR increases initially but subsequently decreases in magnitude during prolonged leg cycling. Additionally, we tested the role of cutaneous vasodilation in the elimination of increased retrograde SR during prolonged exercise. Brachial artery diameter and velocity profiles and forearm skin blood flow and temperature were measured at rest and during 50 min of steady-state, semirecumbent leg cycling (120 W) in 14 males. Exercise decreased forearm vascular conductance (FVC) and increased retrograde SR at 5 min (both P < 0.05), but subsequently forearm and cutaneous vascular conductance (CVC) rose while retrograde SR returned toward baseline values. The elimination of increased retrograde SR was related to the increase in FVC ( r2= 0.58; P < 0.05) and CVC ( r2= 0.32; P < 0.05). Moreover, when the forearm was cooled via a water-perfused suit between minutes 30 and 40 to blunt cutaneous vasodilation attending exercise, FVC was reduced and the magnitude of retrograde SR was increased from −49.7 ± 13.6 to −78.4 ± 16.5 s−1( P < 0.05). Importantly, these responses resolved with removal of cooling during the final 10 min of exercise (retrograde SR: −46.9 ± 12.5 s−1). We conclude that increased brachial artery retrograde SR at the onset of leg cycling subsequently returns toward baseline values due in part to thermoregulatory cutaneous vasodilation during prolonged exercise.


2012 ◽  
Vol 44 (6) ◽  
pp. 1035-1042 ◽  
Author(s):  
ERIKA IWAMOTO ◽  
KEISHO KATAYAMA ◽  
YOSHIHARU OSHIDA ◽  
KOJI ISHIDA

2021 ◽  
Vol 130 (1) ◽  
pp. 17-25
Author(s):  
Jennifer L. Petterson ◽  
Myles W. O’Brien ◽  
Jarrett A. Johns ◽  
Jack Chiasson ◽  
Derek S. Kimmerly

We compared changes in upper- and lower-limb artery endothelial-dependent vasodilatory and vasoconstrictor responses between control, prostaglandin inhibition, and endothelial-derived hyperpolarizing factor inhibition conditions. Neither prostaglandins nor endothelial-derived hyperpolarizing factor influenced flow-mediated dilation responses in either the brachial or popliteal artery. In contrast, endothelial-derived hyperpolarizing factor, but not prostaglandins, reduced resting brachial artery blood flow and shear rate and resting popliteal artery diameter, as well as low-flow-mediated constriction responses in both the popliteal and brachial arteries.


2005 ◽  
Vol 98 (6) ◽  
pp. 2185-2190 ◽  
Author(s):  
M. Rakobowchuk ◽  
C. L. McGowan ◽  
P. C. de Groot ◽  
J. W. Hartman ◽  
S. M. Phillips ◽  
...  

Given the increasing emphasis on performance of resistance exercise as an essential component of health, we evaluated, using a prospective longitudinal design, the potential for resistance training to affect arterial endothelial function. Twenty-eight men (23 ± 3.9 yr old; mean ± SE) engaged in 12 wk of whole body resistance training five times per week using a repeating split-body 3-day cycle. Brachial endothelial function was measured using occlusion cuff-induced flow-mediated dilation. After occlusion of the forearm for 4.5 min, brachial artery dilation and postocclusion blood flow was measured continuously for 15 and 70 s, respectively. Peak and 10-s postocclusion blood flow, shear rate, and brachial artery flow-mediated dilation (relative and normalized to shear rate) were measured pretraining (Pre), at 6 wk of training (Mid), and at 13 wk of training (Post). Results indicated an increase of mean brachial artery diameter by Mid and Post vs. Pre. Peak and 10-s postocclusion blood flow increased by Mid and remained elevated at Post; however, shear rates were not different at any time point. Relative and normalized flow-mediated dilation was also not different at any time point. This study is the first to show that peripheral arterial remodeling does occur with resistance training in healthy young men. In addition, the increase in postocclusion blood flow may indicate improved resistance vessel function. However, unlike studies involving endurance training, flow-mediated dilation did not increase with resistance training. Thus arterial adaptations with high-pressure loads, such as those experienced during resistance exercise, may be quite different compared with endurance training.


2011 ◽  
Vol 43 (Suppl 1) ◽  
pp. 746
Author(s):  
Lauro C. Vianna ◽  
Jaume Padilla ◽  
Grant H. Simmons ◽  
Michael J. Davis ◽  
M Harold Laughlin ◽  
...  

2013 ◽  
Vol 113 (10) ◽  
pp. 2565-2575 ◽  
Author(s):  
Erika Iwamoto ◽  
Keisho Katayama ◽  
Shin Yamashita ◽  
Yoshiharu Oshida ◽  
Koji Ishida

2015 ◽  
Vol 100 (4) ◽  
pp. 463-474 ◽  
Author(s):  
Nathalie M. M. Benda ◽  
Joost P. H. Seeger ◽  
Dirk P. T. van Lier ◽  
Louise Bellersen ◽  
Arie P. J. van Dijk ◽  
...  

2020 ◽  
Vol 70 (1) ◽  
Author(s):  
Kohei Miura ◽  
Hideaki Kashima ◽  
Anna Oue ◽  
Ayaka Kondo ◽  
Sachiko Watanabe ◽  
...  

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