Skeletal muscle blood flow responses to hypoperfusion at rest and during rhythmic exercise in humans

Author:

Casey Darren P.,Joyner Michael J.

Abstract

We evaluated the contribution of changes in systemic arterial pressure and local vasodilation to blood flow restoration in contracting human muscles during acute hypoperfusion. Healthy subjects ( n = 10) performed rhythmic forearm exercise (10% and 20% of maximum) while a balloon in the brachial artery located above the elbow was inflated. Each trial included 3 min of rest, exercise, exercise with balloon inflation, and exercise after balloon deflation. Forearm blood flow (FBF) was measured using Doppler ultrasound. Blood pressure on both sides of the balloon was measured using a brachial artery catheter (distal pressure), and Finometer for proximal (systemic) arterial pressure. Balloon inflation during exercise reduced distal arterial pressure, and FBF fell 37–41%. There was also a surprising acute increase in forearm vascular resistance (distal pressure/FBF). This was followed by recovery of distal arterial pressure and forearm vasodilation that caused a marked (∼75%) restoration of flow that was not associated with significant changes in systemic arterial pressure. During validation trials ( n = 6) at rest and with exercise both balloon and brachial artery diameters were stable when the balloon was inflated. Our findings indicate that at these exercise intensities 1) the restoration of FBF during exercise with hypoperfusion relied primarily on local dilator responses in conjunction with restoration of distal perfusion pressure likely as a result of increased collateral flow around the elbow, and 2) a loss of pulsatile flow and elastic recoil in the forearm may have contributed to the acute increase in vascular resistance seen at the onset of hypoperfusion.

Publisher

American Physiological Society

Subject

Physiology (medical),Physiology

Cited by 22 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3