AJP - Regu Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Regul Integr Comp Physiol 274: R318-R323, 1998;
0363-6119/98 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Coleman, M. J.
Right arrow Articles by Dampney, R. A. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Coleman, M. J.
Right arrow Articles by Dampney, R. A. L.
Vol. 274, Issue 2, R318-R323, February 1998

Sympathoinhibition evoked from caudal midline medulla is mediated by GABA receptors in rostral VLM

Matthew J. Coleman1 and Roger A. L. Dampney2

Departments of 1 Biomedical Sciences and 2 Physiology and Institute for Biomedical Research, University of Sydney, New South Wales 2006, Australia

The present study was performed to determine whether the powerful depressor and sympathoinhibitory response that can be evoked from neurons in the caudal midline medulla is mediated by gamma -aminobutyric acidergic (GABAergic) inhibition of sympathoexcitatory neurons in the rostral part of the ventrolateral medulla (VLM). In anesthetized barointact and barodenervated rabbits, bilateral microinjections of bicuculline into sympathoexcitatory sites in the rostral VLM resulted in a sustained increase in renal sympathetic nerve activity and abolished or reversed the depressor and sympathoinhibitory response evoked by glutamate microinjection into the caudal midline medulla. By contrast, the sympathoinhibitory response evoked from the caudal midline medulla persisted when the background level of renal sympathetic nerve activity was reflexly raised by baroreceptor unloading. The results indicate that 1) the depressor and sympathoinhibitory response evoked by stimulation of neurons in the caudal midline medulla is mediated by a GABAergic synapse in the rostral VLM and 2) there are also sympathoexcitatory neurons in the caudal midline medulla whose presence is revealed by blockade of the more powerful sympathoinhibitory response.

gamma -aminobutyric acid; ventrolateral medulla; baroreceptor reflex; raphe pallidus and obscurus; renal sympathetic nerve activity


This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
S. M. Barman and G. L. Gebber
Role of ventrolateral medulla in generating the 10-Hz rhythm in sympathetic nerve discharge
Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2007; 293(1): R223 - R233.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
C. Dean
Sympathoinhibition from ventrolateral periaqueductal gray mediated by the caudal midline medulla
Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2005; 289(5): R1477 - R1481.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
T. A. Verner, A. K. Goodchild, and P. M. Pilowsky
A mapping study of cardiorespiratory responses to chemical stimulation of the midline medulla oblongata in ventilated and freely breathing rats
Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2004; 287(2): R411 - R421.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. R. Potas and R. A. L. Dampney
Sympathoinhibitory pathway from caudal midline medulla to RVLM is independent of baroreceptor reflex pathway
Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2003; 284(4): R1071 - R1078.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. A. Moffitt, C. M. Heesch, and E. M. Hasser
Increased GABAA inhibition of the RVLM after hindlimb unloading in rats
Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2002; 283(3): R604 - R614.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
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]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
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]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
A. J. M. Verberne, D. M. Sartor, and A. Berke
Midline medullary depressor responses are mediated by inhibition of RVLM sympathoexcitatory neurons in rats
Am J Physiol Regulatory Integrative Comp Physiol, April 1, 1999; 276(4): R1054 - R1062.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online