Journal article
Muscle contraction induced arterial shear stress increases endothelial nitric oxide synthase phosphorylation in humans
American journal of physiology. Heart and circulatory physiology, Vol.313(4), pp.H854-859
10/01/2017
DOI: 10.1152/ajpheart.00282.2017
PMCID: PMC5668602
PMID: 28801524
Abstract
We determined if local increases in brachial artery shear during repetitive muscle contractions induce changes in protein expression of endothelial nitric oxide synthase (eNOS) and/or phosphorylated (p-)eNOS at Ser
, the primary activation site on eNOS, in endothelial cells (ECs) of humans. Seven young male subjects (25 ± 1 yr) performed 20 separate bouts (3 min each) of rhythmic forearm exercise at 20% of maximum over a 2-h period. Each bout of exercise was separated by 3 min of rest. An additional six male subjects (24 ± 1 yr) served as time controls (no exercise). ECs were freshly isolated from the brachial artery using sterile J-wires through an arterial catheter at baseline and again after the 2-h exercise or time control period. Expression of eNOS or p-eNOS Ser
in ECs was determined via immunofluorescence. Brachial artery mean shear rate was elevated compared with baseline and the time control group throughout the 2-h exercise protocol (
< 0.001). p-eNOS Ser
expression was increased 57% in ECs in the exercise group [0.06 ± 0.01 vs. 0.10 ± 0.02 arbitrary units (au),
= 0.02] but not in the time control group (0.08 ± 0.01 vs. 0.07 ± 0.01 au,
= 0.72). In contrast, total eNOS expression did not change in either the exercise (0.13 ± 0.04 vs. 0.12 ± 0.03 au) or time control (0.12 ± 0.03 vs. 0.11 ± 0.03 au) group (
> 0.05 for both). Our novel results suggest that elevations in brachial artery shear increase eNOS Ser
phosphorylation in the absence of changes in total eNOS in ECs of young healthy male subjects, suggesting that this model is sufficient to alter posttranslational modification of eNOS activity in vivo in humans.
Elevations in brachial artery shear in response to forearm exercise increased endothelial nitric oxide synthase Ser
phosphorylation in brachial artery endothelial cells of healthy humans. Our present study provides the first evidence in humans that muscle contraction-induced increases in conduit arterial shear lead to in vivo posttranslational modification of endothelial nitric oxide synthase activity in endothelial cells.
Details
- Title: Subtitle
- Muscle contraction induced arterial shear stress increases endothelial nitric oxide synthase phosphorylation in humans
- Creators
- Darren P Casey - Fraternal Order of Eagles Diabetes Research, University of Iowa, Iowa City, Iowa; andKenichi Ueda - Department of Anesthesia, University of Iowa, Iowa City, IowaLauren Wegman-Points - Department of Health and Human Physiology, University of Iowa, Iowa City, IowaGary L Pierce - Fraternal Order of Eagles Diabetes Research, University of Iowa, Iowa City, Iowa; and
- Resource Type
- Journal article
- Publication Details
- American journal of physiology. Heart and circulatory physiology, Vol.313(4), pp.H854-859
- Publisher
- United States
- DOI
- 10.1152/ajpheart.00282.2017
- PMID
- 28801524
- PMCID
- PMC5668602
- ISSN
- 0363-6135
- eISSN
- 1522-1539
- Grant note
- P30 ES005605 / NIEHS NIH HHS
- Language
- English
- Date published
- 10/01/2017
- Academic Unit
- Anesthesia; Physical Therapy and Rehabilitation Science; Health and Human Physiology; Internal Medicine
- Record Identifier
- 9984002370902771
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