| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Department of Autonomic Neuroscience, Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan
Astronauts usually work under much mental stress. However, it is unclear how and whether or not an exposure to microgravity affects physiological response to mental stress in humans. To examine effects of microgravity on vasomotor sympathetic and peripheral vasodilator responses to mental stress, we performed 10 min of mental arithmetic (MA) before and after 14 days of 6° head-down bed rest (HDBR), a ground-based simulation of spaceflight. Total muscle sympathetic nerve activity (MSNA, measured by microneurography) slightly increased during MA before HDBR, and this increase was augmented after HDBR. Calf blood flow (measured by venous occlusion plethysmography) increased and calf vascular resistance (calculated by dividing mean blood pressure by calf blood flow) decreased during MA before HDBR, but these responses were abolished after HDBR. Increases in heart rate and mean blood pressure during MA were not different between before and after HDBR. These findings suggest that HDBR augmented vasomotor sympathoexcitation but attenuated vasodilatation in the calf muscle in response to mental stress.
muscle sympathetic nerve activity; blood flow; vascular resistance; microgravity
This article has been cited by other articles:
|
|
 |
|
  N. T. Kuipers, C. L. Sauder, J. R. Carter, and C. A. Ray Neurovascular responses to mental stress in the supine and upright postures J Appl Physiol, April 1, 2008; 104(4): 1129 - 1136. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. R. Carter and J. E. Lawrence Effects of the menstrual cycle on sympathetic neural responses to mental stress in humans J. Physiol., December 1, 2007; 585(2): 635 - 641. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R Carter, N. T Kupiers, and C. A Ray Neurovascular responses to mental stress J. Physiol., April 1, 2005; 564(1): 321 - 327. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. M. Stewart, M. S. Medow, L. D. Montgomery, and K. McLeod Decreased skeletal muscle pump activity in patients with postural tachycardia syndrome and low peripheral blood flow Am J Physiol Heart Circ Physiol, March 1, 2004; 286(3): H1216 - H1222. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. L. Olive, J. M. Slade, G. A. Dudley, and K. K. McCully Blood flow and muscle fatigue in SCI individuals during electrical stimulation J Appl Physiol, February 1, 2003; 94(2): 701 - 708. [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]
|
|
|
|
 |
|
 P. A. Lanfranchi and V. K Somers Arterial baroreflex function and cardiovascular variability: interactions and implications Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2002; 283(4): R815 - R826. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. M. Stauss Baroreceptor reflex function Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2002; 283(2): R284 - R286. [Full Text] [PDF]
|
|
|
|
 |
|
 D. Lucini, G. Norbiato, M. Clerici, and M. Pagani Hemodynamic and Autonomic Adjustments to Real Life Stress Conditions in Humans Hypertension, January 1, 2002; 39(1): 184 - 188. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
