(Hypertension. 2000;36:383.)
© 2000 American Heart Association, Inc.
Scientific Contributions |
Interaction of Carbon Dioxide and Sympathetic Nervous System Activity in the Regulation of Cerebral Perfusion in Humans
From the Clinical Research Center, Franz-Volhard Clinic, Humboldt University, Berlin, Germany (J.J.), and the Autonomic Dysfunction Center, Vanderbilt University, Nashville, Tenn.
Correspondence to Jens Jordan, MD, Clinical Research Center, Franz-Volhard Clinic, Humboldt University, Wiltbergstr 50, 13125 Berlin, Germany. E-mail jordan{at}fvk-berlin.de
Abstract—Recent studies suggest that activation of the sympathetic nervous system either directly or indirectly influences cerebrovascular tone in humans even within the autoregulatory range. In 6 healthy subjects (aged 29±4 years), we used transcranial Doppler sonography to determine cerebral blood flow velocity during sympathetic activation elicited through head-up tilt (HUT) and sympathetic deactivation through ganglionic blockade. PaCO2 was manipulated through hyperventilation and CO2 breathing (5%). With subjects in the supine position and during HUT, mean arterial pressure was not influenced by PaCO2. During ganglionic blockade, mean arterial pressure decreased markedly with hyperventilation (-13±1.9 mm Hg). Manipulation of sympathetic tone elicited only mild changes in cerebral blood flow (64±5.8 cm/s supine, 58±4.9 cm/s upright, and 66±6.2 cm/s during ganglionic blockade; P=0.07 by ANOVA). The slope of the regression between PaCO2 and mean velocity was 1.6±0.18 cm/(s · mm Hg) supine, 1.3±0.14 cm/(s · mm Hg) during HUT, and 2.3±0.36 cm/(s · mm Hg) during ganglionic blockade (P<0.05). Spontaneous PaCO2 and ventilatory response to hypercapnia were also modulated by the level of sympathetic activity. Changes in sympathetic tone have a limited effect on cerebral blood flow at normal PaCO2 levels. However, the sympathetic nervous system seems to attenuate the CO2-induced increase in cerebral blood flow. This phenomenon may indicate a moderate direct effect of the sympathetic nervous system on the cerebral vasculature. Furthermore, sympathetic activation tends to increase ventilation and thus can indirectly increase cerebrovascular tone.
Key Words: carbon dioxide • baroreflex • receptors, adrenergic • phenylephrine • sympathetic nervous system
This article has been cited by other articles:
 |
|
 |
|
  S. Ogoh and P. N. Ainslie Cerebral blood flow during exercise: mechanisms of regulation J Appl Physiol, November 1, 2009; 107(5): 1370 - 1380. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. J. Ocon, M. S. Medow, I. Taneja, D. Clarke, and J. M. Stewart Decreased upright cerebral blood flow and cerebral autoregulation in normocapnic postural tachycardia syndrome Am J Physiol Heart Circ Physiol, August 1, 2009; 297(2): H664 - H673. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. N. Ainslie and J. Duffin Integration of cerebrovascular CO2 reactivity and chemoreflex control of breathing: mechanisms of regulation, measurement, and interpretation Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2009; 296(5): R1473 - R1495. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Strandgaard and S. T. Sigurdsson Counterpoint: Sympathetic nerve activity does not influence cerebral blood flow J Appl Physiol, October 1, 2008; 105(4): 1366 - 1367. [Full Text] [PDF]
|
|
|
|
|
|
B. D. Levine, R. Zhang, M. Visocchi, P. N. Ainslie, S. Ogoh, L. Edvinsson, M. Yildiz, O. B. Paulson, G. M. Knudsen, P. A. Cassaglia, et al. Comments on Point:Counterpoint: Sympathetic activity does/does not influence cerebral blood flow J Appl Physiol, October 1, 2008; 105(4): 1369 - 1373. [Full Text] [PDF]
|
|
|
|
|
|
Rebuttal from Strandgaard and Sigurdsson J Appl Physiol, October 1, 2008; 105(4): 1367 - 1368. [Full Text] [PDF]
|
|
|
|
|
|
R. D. Thijs, J. G. van den Aardweg, R. H. A. M. Reijntjes, J. G. van Dijk, and J. J. van Lieshout Contrasting effects of isocapnic and hypocapnic hyperventilation on orthostatic circulatory control J Appl Physiol, October 1, 2008; 105(4): 1069 - 1075. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Ogoh, N. Hayashi, M. Inagaki, P. N. Ainslie, and T. Miyamoto Interaction between the ventilatory and cerebrovascular responses to hypo- and hypercapnia at rest and during exercise J. Physiol., September 1, 2008; 586(17): 4327 - 4338. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Ogoh, R. M. Brothers, W. L. Eubank, and P. B. Raven Autonomic Neural Control of the Cerebral Vasculature: Acute Hypotension Stroke, July 1, 2008; 39(7): 1979 - 1987. [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]
|
|
|
|
|
|
J. A. H. R. Claassen, R. Zhang, Q. Fu, S. Witkowski, and B. D. Levine Transcranial Doppler estimation of cerebral blood flow and cerebrovascular conductance during modified rebreathing J Appl Physiol, March 1, 2007; 102(3): 870 - 877. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. S. Vantanajal, J. C. Ashmead, T. J. Anderson, R. T. Hepple, and M. J. Poulin Differential sensitivities of cerebral and brachial blood flow to hypercapnia in humans J Appl Physiol, January 1, 2007; 102(1): 87 - 93. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. D. Mitsis, R. Zhang, B. D. Levine, and V. Z. Marmarelis Cerebral hemodynamics during orthostatic stress assessed by nonlinear modeling J Appl Physiol, July 1, 2006; 101(1): 354 - 366. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R D Thijs and J G van Dijk Stress induced hypotension in pure autonomic failure J. Neurol. Neurosurg. Psychiatry, April 1, 2006; 77(4): 552 - 553. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. M. Gupta, P. K. Bithal, H. H. Dash, A. Chaturvedi, and R. P. Mahajan Effects of stellate ganglion block on cerebral haemodynamics as assessed by transcranial Doppler ultrasonography Br. J. Anaesth., November 1, 2005; 95(5): 669 - 673. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Kotajima, G. E Meadows, M. J Morrell, and D. R Corfield Cerebral blood flow changes associated with fluctuations in alpha and theta rhythm during sleep onset in humans J. Physiol., October 1, 2005; 568(1): 305 - 313. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Xie, J. B. Skatrud, R. Khayat, J. A. Dempsey, B. Morgan, and D. Russell Cerebrovascular Response to Carbon Dioxide in Patients with Congestive Heart Failure Am. J. Respir. Crit. Care Med., August 1, 2005; 172(3): 371 - 378. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. N Ainslie, J. C Ashmead, K. Ide, B. J Morgan, and M. J Poulin Differential responses to CO2 and sympathetic stimulation in the cerebral and femoral circulations in humans J. Physiol., July 15, 2005; 566(2): 613 - 624. [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]
|
|
|
|
|
|
I. K. Moppett, M. J. Wild, R. W. Sherman, J. A. Latter, K. Miller, and R. P. Mahajan Effects of ephedrine, dobutamine and dopexamine on cerebral haemodynamics: transcranial Doppler studies in healthy volunteers Br. J. Anaesth., January 1, 2004; 92(1): 39 - 44. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. LeMarbre, S. Stauber, R. N Khayat, D. S Puleo, J. B Skatrud, and B. J Morgan Baroreflex-induced sympathetic activation does not alter cerebrovascular CO2 responsiveness in humans J. Physiol., September 1, 2003; 551(2): 609 - 616. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Lavi, R. Egbarya, R. Lavi, and G. Jacob Role of Nitric Oxide in the Regulation of Cerebral Blood Flow in Humans: Chemoregulation Versus Mechanoregulation Circulation, April 15, 2003; 107(14): 1901 - 1905. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Przyby{nmid}owski, M.-F. Bangash, K. Reichmuth, B. J Morgan, J. B Skatrud, and J. A Dempsey Mechanisms of the cerebrovascular response to apnoea in humans J. Physiol., April 1, 2003; 548(1): 323 - 332. [Abstract] [Full Text] [PDF]
|
|