NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Carotid baroreflex regulation of sympathetic nerve activity during dynamic exercise in humansWe sought to determine whether carotid baroreflex (CBR) control of muscle sympathetic nerve activity (MSNA) was altered during dynamic exercise. In five men and three women, 23.8 +/- 0.7 (SE) yr of age, CBR function was evaluated at rest and during 20 min of arm cycling at 50% peak O(2) uptake using 5-s periods of neck pressure and neck suction. From rest to steady-state arm cycling, mean arterial pressure (MAP) was significantly increased from 90.0 +/- 2.7 to 118.7 +/- 3.6 mmHg and MSNA burst frequency (microneurography at the peroneal nerve) was elevated by 51 +/- 14% (P < 0.01). However, despite the marked increases in MAP and MSNA during exercise, CBR-Delta%MSNA responses elicited by the application of various levels of neck pressure and neck suction ranging from +45 to -80 Torr were not significantly different from those at rest. Furthermore, estimated baroreflex sensitivity for the control of MSNA at rest was the same as during exercise (P = 0.74) across the range of neck chamber pressures. Thus CBR control of sympathetic nerve activity appears to be preserved during moderate-intensity dynamic exercise.
Document ID
20040112582
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Fadel, P. J.
(Department of Integrative Physiology and Cardiovascular Research Institute, University of North Texas Health Science Center Fort Worth, Texas 76107, United States)
Ogoh, S.
Watenpaugh, D. E.
Wasmund, W.
Olivencia-Yurvati, A.
Smith, M. L.
Raven, P. B.
Date Acquired
August 21, 2013
Publication Date
March 1, 2001
Publication Information
Publication: American journal of physiology. Heart and circulatory physiology
Volume: 280
Issue: 3
ISSN: 0363-6135
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: HL-45547
Distribution Limits
Public
Copyright
Other
Keywords
Non-NASA Center
NASA Discipline Cardiopulmonary

Available Downloads

There are no available downloads for this record.
No Preview Available