| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Departments of Psychology and Pharmacology and Cardiovascular Center, University of Iowa, Iowa City, Iowa 52242; and 2 Department of Nephrology, University of Erlangen/Nürnberg, Erlangen 91052, Germany
Mean arterial
pressure (MAP), heart rate (HR), and renal sympathetic nerve activity
(RSNA) were measured in conscious rats during either hemorrhage or
cardiopulmonary chemoreceptor stimulation with phenylbiguanide (PBG)
after intracerebroventricular injection of the
5-HT1/5-HT2-receptor
antagonist, methysergide (40 µg). Progressive hemorrhage
caused an initial rise (109 ± 33%) followed by a fall in RSNA
(
60 ± 7%) and a fall in HR (126 ± 7 beats/min). Methysergide delayed the hypotension and prevented both the
sympathoinhibitory and bradycardic responses to hemorrhage. Systemic
5-HT3-receptor blockade did not
influence responses to hemorrhage. The PBG infusion caused transient
depressor (25 ± 6 mmHg), bradycardic (176 ± 40 beats/min), and renal sympathostimulatory (182 ± 47% baseline) responses that were not affected by central methysergide (20 ± 6 mmHg, 162 ± 18 beats/min, 227 ± 46% baseline).
These data indicate that a central serotonergic receptor-mediated
component contributes to the sympathoinhibitory and bradycardic
responses to hypotensive hemorrhage in conscious rats. Furthermore, the same central 5-HT-receptor populations involved in reflex responses to
hypotensive hemorrhage probably do not mediate the sympathoinhibitory response to cardiopulmonary chemosensitive
5-HT3 receptors.
phenylbiguanide; renal sympathetic nerve activity
This article has been cited by other articles:
|
|
 |
|
  R. Tiniakov and K. E. Scrogin The spleen is required for 5-HT1A receptor agonist-mediated increases in mean circulatory filling pressure during hemorrhagic shock in the rat Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2009; 296(5): R1392 - R1401. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Blair and D. Mickelsen Activation of lateral parabrachial nucleus neurons restores blood pressure and sympathetic vasomotor drive after hypotensive hemorrhage Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2006; 291(3): R742 - R750. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. C. Schadt, H. L. Shafford, and M. D. McKown Neuronal activity within the ventrolateral periaqueductal gray during simulated hemorrhage in conscious rabbits Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2006; 290(3): R715 - R725. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Ditting, K. F. Hilgers, K. E. Scrogin, A. Stetter, P. Linz, and R. Veelken Mechanosensitive cardiac C-fiber response to changes in left ventricular filling, coronary perfusion pressure, hemorrhage, and volume expansion in rats Am J Physiol Heart Circ Physiol, February 1, 2005; 288(2): H541 - H552. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. C. Schadt What is the role of serotonin during hemorrhage in conscious animals? Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2003; 284(3): R780 - R781. [Full Text] [PDF]
|
|
|
|
|
|
C. Dean and M. Bago Renal sympathoinhibition mediated by 5-HT1A receptors in the RVLM during severe hemorrhage in rats Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2002; 282(1): R122 - R130. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Cavun and W. R. Millington Evidence that hemorrhagic hypotension is mediated by the ventrolateral periaqueductal gray region Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2001; 281(3): R747 - R752. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Blair, R. L. Jaworski, A. Want, and D. T. Piekut Parabrachial nucleus modulates cardiovascular responses to blood loss Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2001; 280(4): R1141 - R1148. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. E. Scrogin, A. K. Johnson, and V. L. Brooks Methysergide delays the decompensatory responses to severe hemorrhage by activating 5-HT1A receptors Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2000; 279(5): R1776 - R1786. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. J. Scislo and D. S. O'Leary Differential role of ionotropic glutamatergic mechanisms in responses to NTS P2x and A2a receptor stimulation Am J Physiol Heart Circ Physiol, June 1, 2000; 278(6): H2057 - H2068. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. J. Scislo and D. S. O'Leary Differential control of renal vs. adrenal sympathetic nerve activity by NTS A2a and P2x purinoceptors Am J Physiol Heart Circ Physiol, December 1, 1998; 275(6): H2130 - H2139. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
