| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 University of North Texas Health Science Center at Fort Worth, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
Carotid baroreflex (CBR) function was examined in five men and three women (25 ± 1 years) using the variable-pressure neck collar technique at rest and during dynamic, one-legged knee extension exercise at 7 W and 25 W. The CBR exhibited control of leg vascular conductance (LVC) at rest and during exercise in both an exercising leg (EL) and a non-exercising leg (NEL) across a wide range of pressures from +40 Torr neck pressure (NP) to –80 Torr neck suction (NS). Specifically, increases in LVC (% change) in response to NS were no different across –20 to –80 Torr in either EL or NEL compared to rest, P > 0.05. However, CBR-mediated decreases in percentage LVC in response to NP were attenuated in EL at both 7 W (16 ± 1%) and 25 W (12 ± 1%) compared to rest (40 ± 3%; P < 0.05) as well as compared to responses in the NEL (36 ± 6% at 7 W and 36 ± 7% at 25 W; P < 0.05). This decrease in vascular responsiveness in EL was associated with a reduction in the gain of the percentage muscle sympathetic nerve activity (%MSNA)–%LVC relationship compared to rest (P < 0.05). Collectively, these data indicate that, despite a clear attenuation of the vascular response to MSNA in the exercising leg, CBR-mediated changes in mean arterial pressure were no different between rest and exercise.
(Received 15 July 2004;
accepted after revision 20 September 2004;
first published online 23 September 2004)
Corresponding author D. M. Keller: Institute for Exercise and Environmental Medicine, 7232 Greenville Ave, Dallas, TX 75231, USA. Email: davidkeller{at}texashealth.org
This article has been cited by other articles:
|
|
 |
|
  M. Ichinose, M. Saito, N. Fujii, T. Ogawa, K. Hayashi, N. Kondo, and T. Nishiyasu Modulation of the control of muscle sympathetic nerve activity during incremental leg cycling J. Physiol., June 1, 2008; 586(11): 2753 - 2766. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Ogoh, J. P. Fisher, P. B. Raven, and P. J. Fadel Arterial baroreflex control of muscle sympathetic nerve activity in the transition from rest to steady-state dynamic exercise in humans Am J Physiol Heart Circ Physiol, October 1, 2007; 293(4): H2202 - H2209. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. K. Pellinger and J. R. Halliwill Effect of propranolol on sympathetically mediated leg vasoconstriction in humans J. Physiol., September 1, 2007; 583(2): 797 - 809. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. M. McDowall and R. A. L. Dampney Calculation of threshold and saturation points of sigmoidal baroreflex function curves Am J Physiol Heart Circ Physiol, October 1, 2006; 291(4): H2003 - H2007. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Ogoh, R. M. Brothers, Q. Barnes, W. L. Eubank, M. N. Hawkins, S. Purkayastha, A. O-Yurvati, and P. B. Raven Effects of changes in central blood volume on carotid-vasomotor baroreflex sensitivity at rest and during exercise J Appl Physiol, July 1, 2006; 101(1): 68 - 75. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. B Raven, P. J Fadel, and S. Ogoh Arterial baroreflex resetting during exercise: a current perspective Exp Physiol, January 1, 2006; 91(1): 37 - 49. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. M. Keller, S. Ogoh, S. Greene, A Olivencia-Yurvati, and P. B Raven Inhibition of KATP channel activity augments baroreflex-mediated vasoconstriction in exercising human skeletal muscle J. Physiol., November 15, 2004; 561(1): 273 - 282. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
