|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Themed Issue Papers |
1 Department of Biomedical Science, Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO 65211, USA
Inhibitory neurotransmission plays a crucial role in the processing of sensory afferent signals in the nucleus of the solitary tract (NTS). The aim of this review is to provide a critical overview of inhibitory mechanisms that may be responsible for altering arterial baroreflex function during physical activity or exercise. Over a decade ago, the view of reflex control of cardiovascular function during exercise was revised because of the finding that the arterial baroreflex is reset in humans, enabling continuous beat-to-beat reflex regulation of blood pressure and heart rate. During the ensuing decade, many investigators proposed that resetting was mediated by central neural mechanisms that were intrinsic to the brain. Recent experimental data suggest that rapid and reversible changes in
-aminobutyric acid (GABA) inhibitory neurotransmission within the NTS play a fundamental role in this process. The hypothesis will be presented that baroreflex resetting by somatosensory input is mediated by: (1) selective inhibition of barosensitive NTS neurones; and (2) excitation of sympathoexcitatory neurones in the rostral ventrolateral medulla. Current research findings will be discussed that support an interaction between GABA and substance P (SP) signalling mechanisms in the NTS. An understanding of these mechanisms may prove to be essential for future detailed analysis of the cellular and molecular mechanisms underlying sensory integration in the NTS.
(Received 14 September 2005;
accepted after revision 5 October 2005; first published online 20 October 2005)
Corresponding author J. T. Potts: Department of Biomedical Science, College of Veterinary Medicine, Dalton Cardiovascular Research Center, University of Missouri, 134 Research Park Drive, Columbia, MO 65211, USA. Email: pottsjt{at}missouri.edu
This article has been cited by other articles:
![]() |
J. P. Fisher, C. N. Young, and P. J. Fadel Effect of muscle metaboreflex activation on carotid-cardiac baroreflex function in humans Am J Physiol Heart Circ Physiol, May 1, 2008; 294(5): H2296 - H2304. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. P. Fisher, S. Ogoh, C. N. Young, D. M. Keller, and P. J. Fadel Exercise intensity influences cardiac baroreflex function at the onset of isometric exercise in humans J Appl Physiol, September 1, 2007; 103(3): 941 - 947. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Herigstad, G. M. Balanos, and P. A. Robbins Can human cardiovascular regulation during exercise be learnt from feedback from arterial baroreceptors? Exp Physiol, July 1, 2007; 92(4): 695 - 704. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Sala-Mercado, M. Ichinose, R. L. Hammond, T. Ichinose, M. Pallante, L. W. Stephenson, D. S. O'Leary, and F. Iellamo Muscle metaboreflex attenuates spontaneous heart rate baroreflex sensitivity during dynamic exercise Am J Physiol Heart Circ Physiol, June 1, 2007; 292(6): H2867 - H2873. [Abstract] [Full Text] [PDF] |
||||
![]() |
W.-Z. Wang, L. Gao, Y.-X. Pan, I. H. Zucker, and W. Wang AT1 receptors in the nucleus tractus solitarii mediate the interaction between the baroreflex and the cardiac sympathetic afferent reflex in anesthetized rats Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2007; 292(3): R1137 - R1145. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. B Raven Neural Control of the Circulation during Exercise Themed Issue Exp Physiol, January 1, 2006; 91(1): 25 - 26. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |