| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Departments of 1 Medicine and 3 Surgery, University of Wisconsin, and the 2 William S. Middleton Veterans Hospital, Madison, Wisconsin 53705
We examined the neurocirculatory and ventilatory responses to intermittent asphyxia (arterial O2 saturation = 79-85%, end-tidal PCO2 =3-5 Torr above eupnea) in seven healthy humans during wakefulness. The intermittent asphyxia intervention consisted of 20-s asphyxic exposures alternating with 40-s periods of room-air breathing for a total of 20 min. Minute ventilation increased during the intermittent asphyxia period (14.2 ± 2.0 l/min in the final 5 min of asphyxia vs. 7.5 ± 0.4 l/min in baseline) but returned to the baseline level within 2 min after completion of the series of asphyxic exposures. Muscle sympathetic nerve activity increased progressively, reaching 175 ± 12% of baseline in the final 5 min of the intervention. Unlike ventilation, sympathetic activity remained elevated for at least 20 min after removal of the chemical stimuli (150 ± 10% of baseline in the last 5 min of the recovery period). Intermittent asphyxia caused a small, but statistically significant, increase in heart rate (64 ± 4 beats/min in the final 5 min of asphyxia vs. 61 ± 4 beats/min in baseline); however, this increase was not sustained after the return to room-air breathing. These data demonstrate that relatively short-term exposure to intermittent asphyxia causes sympathetic activation that persists after removal of the chemical stimuli. This carryover effect provides a potential mechanism whereby intermittent asphyxia during sleep could lead to chronic sympathetic activation in patients with sleep apnea syndrome.
sympathetic nervous system; hypoxia; hypercapnia
This article has been cited by other articles:
|
|
 |
|
  R. M. Douglas and G. G. Haddad Can O2 Dysregulation Induce Premature Aging? Physiology, December 1, 2008; 23(6): 333 - 349. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Z. Dujic, V. Ivancev, K. Heusser, G. Dzamonja, I. Palada, Z. Valic, J. Tank, A. Obad, D. Bakovic, A. Diedrich, et al. Central chemoreflex sensitivity and sympathetic neural outflow in elite breath-hold divers J Appl Physiol, January 1, 2008; 104(1): 205 - 211. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Buyse, J. Hedner, and the participants of working group 2 Sleep apnoea, hypertension and vascular disease: where are we now? Eur. Respir. Rev., December 1, 2007; 16(106): 169 - 182. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
U. A. Leuenberger, C. S. Hogeman, S. Quraishi, L. Linton-Frazier, and K. S. Gray Short-term intermittent hypoxia enhances sympathetic responses to continuous hypoxia in humans J Appl Physiol, September 1, 2007; 103(3): 835 - 842. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. A. Imadojemu, Z. Mawji, A. Kunselman, K. S. Gray, C. S. Hogeman, and U. A. Leuenberger Sympathetic Chemoreflex Responses in Obstructive Sleep Apnea and Effects of Continuous Positive Airway Pressure Therapy Chest, May 1, 2007; 131(5): 1406 - 1413. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Q. Fu, N. E. Townsend, S. M. Shiller, E. R. Martini, K. Okazaki, S. Shibata, M. J. Truijens, F. A. Rodriguez, C. J. Gore, J. Stray-Gundersen, et al. Intermittent hypobaric hypoxia exposure does not cause sustained alterations in autonomic control of blood pressure in young athletes Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2007; 292(5): R1977 - R1984. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. L. Smith and C. F. Pacchia Sleep Apnoea & Hypertension: Physiological bases for a causal relation: Sleep apnoea and hypertension: role of chemoreflexes in humans Exp Physiol, January 1, 2007; 92(1): 45 - 50. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. E. Foster, M. J. Poulin, and P. J. Hanly Sleep Apnoea & Hypertension: Physiological bases for a causal relation: Intermittent hypoxia and vascular function: implications for obstructive sleep apnoea Exp Physiol, January 1, 2007; 92(1): 51 - 65. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S.-J. C. Lusina, P. M. Kennedy, J. T. Inglis, D. C. McKenzie, N. T. Ayas, and A. W. Sheel Long-term intermittent hypoxia increases sympathetic activity and chemosensitivity during acute hypoxia in humans J. Physiol., September 15, 2006; 575(3): 961 - 970. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. L Cooper, S. B Pearson, C. M Bowker, M. W Elliott, and R Hainsworth Interaction of chemoreceptor and baroreceptor reflexes by hypoxia and hypercapnia - a mechanism for promoting hypertension in obstructive sleep apnoea J. Physiol., October 15, 2005; 568(2): 677 - 687. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Tamisier, A. Anand, L. M. Nieto, D. Cunnington, and J. W. Weiss Arterial pressure and muscle sympathetic nerve activity are increased after two hours of sustained but not cyclic hypoxia in healthy humans J Appl Physiol, January 1, 2005; 98(1): 343 - 349. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. J. Cutler, N. M. Swift, D. M. Keller, W. L. Wasmund, J. R. Burk, and M. L. Smith Periods of intermittent hypoxic apnea can alter chemoreflex control of sympathetic nerve activity in humans Am J Physiol Heart Circ Physiol, November 1, 2004; 287(5): H2054 - H2060. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. N. Ainslie and M. J. Poulin Ventilatory, cerebrovascular, and cardiovascular interactions in acute hypoxia: regulation by carbon dioxide J Appl Physiol, July 1, 2004; 97(1): 149 - 159. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Tamisier, D. Norman, A. Anand, Y. Choi, and J. W. Weiss Evidence of sustained forearm vasodilatation after brief isocapnic hypoxia J Appl Physiol, May 1, 2004; 96(5): 1782 - 1787. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Cutler, N. M. Swift, D. M. Keller, W. L. Wasmund, and M. L. Smith Hypoxia-mediated prolonged elevation of sympathetic nerve activity after periods of intermittent hypoxic apnea J Appl Physiol, February 1, 2004; 96(2): 754 - 761. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. S. M. Ip, H.-F. Tse, B. Lam, K. W. T. Tsang, and W.-K. Lam Endothelial Function in Obstructive Sleep Apnea and Response to Treatment Am. J. Respir. Crit. Care Med., February 1, 2004; 169(3): 348 - 353. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 O. Marrone, A. Salvaggio, M.R. Bonsignore, G. Insalaco, and G. Bonsignore Blood pressure responsiveness to obstructive events during sleep after chronic CPAP Eur. Respir. J., March 1, 2003; 21(3): 509 - 514. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. S. T. LEUNG and T. DOUGLAS BRADLEY Sleep Apnea and Cardiovascular Disease Am. J. Respir. Crit. Care Med., December 15, 2001; 164(12): 2147 - 2165. [Full Text] [PDF]
|
|
|
|
|
|
A. Xie, J. B. Skatrud, D. S. Puleo, and B. J. Morgan Exposure to hypoxia produces long-lasting sympathetic activation in humans J Appl Physiol, October 1, 2001; 91(4): 1555 - 1562. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
