Acute changes in forearm vascular compliance during transient sympatho‐excitation

Abstract The study of vascular regulation often omits important information about the elastic properties of arteries under conditions of pulsatile flow. The purpose of this study was to examine the relationship between muscle sympathetic nerve activity (MSNA), vascular bed compliance, and peripheral...

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Main Authors: T. Dylan Olver, Mark B. Badrov, Matti D. Allen, Nicole S. Coverdale, J. Kevin Shoemaker
Format: Article
Language:English
Published: Wiley 2022-04-01
Series:Physiological Reports
Subjects:
Online Access:https://doi.org/10.14814/phy2.15256
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author T. Dylan Olver
Mark B. Badrov
Matti D. Allen
Nicole S. Coverdale
J. Kevin Shoemaker
author_facet T. Dylan Olver
Mark B. Badrov
Matti D. Allen
Nicole S. Coverdale
J. Kevin Shoemaker
author_sort T. Dylan Olver
collection DOAJ
description Abstract The study of vascular regulation often omits important information about the elastic properties of arteries under conditions of pulsatile flow. The purpose of this study was to examine the relationship between muscle sympathetic nerve activity (MSNA), vascular bed compliance, and peripheral blood flow responses in humans. We hypothesized that increases in MSNA would correlate with reductions in vascular compliance, and that changes in compliance would correspond with changes in peripheral blood flow during sympatho‐excitation. MSNA (microneurography), blood pressure (Finopres), and brachial artery blood flow (Doppler ultrasound), were monitored in six healthy males at baseline and during the last 15 s of voluntary end‐inspiratory, expiratory apneas and 5 min of static handgrip exercise (SHG; 20% maximum voluntary contraction) and 3 min of post‐exercise circulatory occlusion (SHG + PECO; measured in the non‐exercising arm). A lumped Windkessel model was employed to examine vascular bed compliance. During apnea, indices of MSNA were inversely related with vascular compliance, and reductions in compliance correlated with decreased brachial blood flow rate. During SHG, despite increased MSNA, compliance also increased, but was unrelated to increases in blood flow. Neither during SHG nor PECO did indices of MSNA correlate with forearm vascular compliance nor did vascular compliance correlate with brachial flow. However, during PECO, a linear combination of blood pressure and total MSNA was correlated with vascular compliance. These data indicate the elastic components of the forearm vasculature are regulated by adrenergic and myogenic mechanisms during sympatho‐excitation, but in a reflex‐dependent manner.
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spelling doaj.art-7293a8452df648b9ad49ad514c4118b72022-12-22T01:53:16ZengWileyPhysiological Reports2051-817X2022-04-01108n/an/a10.14814/phy2.15256Acute changes in forearm vascular compliance during transient sympatho‐excitationT. Dylan Olver0Mark B. Badrov1Matti D. Allen2Nicole S. Coverdale3J. Kevin Shoemaker4Biomedical Sciences Western College of Veterinary Medicine University of Saskatchewan Saskatoon Saskatchewan CanadaDivision of Cardiology Department of Medicine University Health Network and Sinai Health University of Toronto Toronto Ontario CanadaDepartment of Physical Medicine and Rehabilitation School of Medicine Queen's University Kingston Ontario CanadaSchool of Kinesiology and Health Studies Queen’s University Kingston Ontario CanadaNeurovascular Research Laboratory School of Kinesiology The University of Western Ontario London Ontario CanadaAbstract The study of vascular regulation often omits important information about the elastic properties of arteries under conditions of pulsatile flow. The purpose of this study was to examine the relationship between muscle sympathetic nerve activity (MSNA), vascular bed compliance, and peripheral blood flow responses in humans. We hypothesized that increases in MSNA would correlate with reductions in vascular compliance, and that changes in compliance would correspond with changes in peripheral blood flow during sympatho‐excitation. MSNA (microneurography), blood pressure (Finopres), and brachial artery blood flow (Doppler ultrasound), were monitored in six healthy males at baseline and during the last 15 s of voluntary end‐inspiratory, expiratory apneas and 5 min of static handgrip exercise (SHG; 20% maximum voluntary contraction) and 3 min of post‐exercise circulatory occlusion (SHG + PECO; measured in the non‐exercising arm). A lumped Windkessel model was employed to examine vascular bed compliance. During apnea, indices of MSNA were inversely related with vascular compliance, and reductions in compliance correlated with decreased brachial blood flow rate. During SHG, despite increased MSNA, compliance also increased, but was unrelated to increases in blood flow. Neither during SHG nor PECO did indices of MSNA correlate with forearm vascular compliance nor did vascular compliance correlate with brachial flow. However, during PECO, a linear combination of blood pressure and total MSNA was correlated with vascular compliance. These data indicate the elastic components of the forearm vasculature are regulated by adrenergic and myogenic mechanisms during sympatho‐excitation, but in a reflex‐dependent manner.https://doi.org/10.14814/phy2.15256peripheral blood flowresistancesympatho‐excitationvascular compliance
spellingShingle T. Dylan Olver
Mark B. Badrov
Matti D. Allen
Nicole S. Coverdale
J. Kevin Shoemaker
Acute changes in forearm vascular compliance during transient sympatho‐excitation
Physiological Reports
peripheral blood flow
resistance
sympatho‐excitation
vascular compliance
title Acute changes in forearm vascular compliance during transient sympatho‐excitation
title_full Acute changes in forearm vascular compliance during transient sympatho‐excitation
title_fullStr Acute changes in forearm vascular compliance during transient sympatho‐excitation
title_full_unstemmed Acute changes in forearm vascular compliance during transient sympatho‐excitation
title_short Acute changes in forearm vascular compliance during transient sympatho‐excitation
title_sort acute changes in forearm vascular compliance during transient sympatho excitation
topic peripheral blood flow
resistance
sympatho‐excitation
vascular compliance
url https://doi.org/10.14814/phy2.15256
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AT mattidallen acutechangesinforearmvascularcomplianceduringtransientsympathoexcitation
AT nicolescoverdale acutechangesinforearmvascularcomplianceduringtransientsympathoexcitation
AT jkevinshoemaker acutechangesinforearmvascularcomplianceduringtransientsympathoexcitation