| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Division of Cardiology, Departments of Medicine and of Cellular and Molecular Physiology, General Clinic Research Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
Evidence from animals indicates that skeletal muscle afferents activate the vestibular nuclei and that both vestibular and skeletal muscle afferents have inputs to the ventrolateral medulla. The purpose of the present study was to investigate the interaction between the vestibulosympathetic and skeletal muscle reflexes on muscle sympathetic nerve activity (MSNA) and arterial pressure in humans. MSNA, arterial pressure, and heart rate were measured in 17 healthy subjects in the prone position during three experimental trials. The three trials were 2 min of 1) head-down rotation (HDR) to engage the vestibulosympathetic reflex, 2) isometric handgrip (IHG) at 30% maximal voluntary contraction to activate skeletal muscle afferents, and 3) HDR and IHG performed simultaneously. The order of the three trials was randomized. HDR and IHG performed alone increased total MSNA by 46 ± 16 and 77 ± 24 units, respectively (P < 0.01). During the HDR plus IHG trial, MSNA increased 142 ± 38 units (P < 0.01). This increase was not significantly different from the sum of the individual trials (130 ± 41 units). This finding was also observed with mean arterial pressure (sum = 21 ± 2 mmHg and HDR + IHG = 22 ± 2 mmHg). These findings suggest that there is an additive interaction for MSNA and arterial pressure when the vestibulosympathetic and skeletal muscle reflexes are engaged simultaneously in humans. Therefore, no central modulation exists between these two reflexes with regard to MSNA output in humans.
autonomic nervous system; exercise; muscle sympathetic nerve activity; muscle afferents; neural control; otolith organs
This article has been cited by other articles:
|
|
 |
|
  J. R. Carter and C. A. Ray Sympathetic responses to vestibular activation in humans Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2008; 294(3): R681 - R688. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Abe, K. Tanaka, C. Awazu, and H. Morita Strong galvanic vestibular stimulation obscures arterial pressure response to gravitational change in conscious rats J Appl Physiol, January 1, 2008; 104(1): 34 - 40. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. J. Dyckman, K. D. Monahan, and C. A. Ray Effect of baroreflex loading on the responsiveness of the vestibulosympathetic reflex in humans J Appl Physiol, September 1, 2007; 103(3): 1001 - 1006. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. E. Wilson and C. A. Ray Effect of thermal stress on the vestibulosympathetic reflexes in humans J Appl Physiol, October 1, 2004; 97(4): 1367 - 1370. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. A. Ray and K. D. Monahan Aging, opioid-receptor agonists and antagonists, and the vestibulosympathetic reflex in humans J Appl Physiol, May 1, 2004; 96(5): 1761 - 1766. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. H. Cooke, J. R. Carter, and T. A. Kuusela Human cerebrovascular and autonomic rhythms during vestibular activation Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2004; 286(5): R838 - R843. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. D. Monahan and C. A. Ray Vestibulosympathetic reflex during orthostatic challenge in aging humans Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2002; 283(5): R1027 - R1032. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. Carter, C. A. Ray, and W. H. Cooke Vestibulosympathetic reflex during mental stress J Appl Physiol, October 1, 2002; 93(4): 1260 - 1264. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. D. Monahan and C. A. Ray Interactive effect of hypoxia and otolith organ engagement on cardiovascular regulation in humans J Appl Physiol, August 1, 2002; 93(2): 576 - 580. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
