![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
Vol. 286, Issue 2, 736-741, August 1998
Committee on Clinical Pharmacology and the Department of Anesthesia
and Critical Care, The Pritzker School of Medicine, The University of
Chicago, Chicago, Illinois
Single units in the region of the medial nucleus tractus solitarius
(NTS), responding to electrical stimulation of gastric vagal fibers,
were recorded in an in vitro neonatal rat
brainstem-gastric preparation. 
-Aminobutyric acid (GABA) subreceptor
agonists and antagonists were applied to the gastric and brainstem
compartments of the bath chamber to evaluate the peripheral gastric and
central brainstem GABAergic effects on NTS neuronal activity. The
gastric effects of the GABAA receptor agonist muscimol and
GABAB receptor agonist baclofen were evaluated on 55 tonic
units that received the gastric vagal inputs. For ~58% (32 of 55)
and 38% (21 of 55) of the units observed, muscimol (30 µM;
IC50 = 2.0 µM) and baclofen (30 µM; IC50 = 1.5 µM) in the gastric compartment induced a concentration-dependent inhibition of 36.2 ± 3.1% (mean ± S.E.) and 31.0 ± 2.9% of the control level of the NTS neuronal activity, respectively.
The brainstem effects of muscimol and baclofen were tested on 51 units. For ~90% (46 of 51) and 78% (40 of 51) of the units tested,
muscimol (30 µM; IC50 = 1.3 µM) and baclofen (30 µM;
IC50 = 1.1 µM) in the brainstem compartment produced a
concentration-dependent inhibition of 54.1 ± 3.4% and 48.9 ± 3.5% of the control level, respectively. The remaining NTS units
were not affected by these two GABA agonists. Bicuculline (10 µM) and
saclofen (10 µM), the GABAA and GABAB subreceptor antagonists, competitively antagonized the gastric and
brainstem effects by muscimol and baclofen, respectively. Our results
demonstrated that both GABAA and GABAB
receptors in the stomach and brainstem play an important role in
activity modulation of the medial NTS neurons receiving gastric vagal
inputs in neonatal rats.
This article has been cited by other articles:
|
|
 |
|
  H. Zheng, L. M. Patterson, C. B. Phifer, and H.-R. Berthoud Brain stem melanocortinergic modulation of meal size and identification of hypothalamic POMC projections Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2005; 289(1): R247 - R258. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C.-S. Yuan, S. Mehendale, Y. Xiao, H. H. Aung, J.-T. Xie, and M. K. Ang-Lee The Gamma-Aminobutyric Acidergic Effects of Valerian and Valerenic Acid on Rat Brainstem Neuronal Activity Anesth. Analg., February 1, 2004; 98(2): 353 - 358. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C.-S. Yuan, L. Dey, J.-T. Xie, and H. H. Aung Gastric Effects of Galanin and Its Interaction with Leptin on Brainstem Neuronal Activity J. Pharmacol. Exp. Ther., May 1, 2002; 301(2): 488 - 493. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. D. Smid, R. L. Young, N. J. Cooper, and L. A. Blackshaw GABABR expressed on vagal afferent neurones inhibit gastric mechanosensitivity in ferret proximal stomach Am J Physiol Gastrointest Liver Physiol, December 1, 2001; 281(6): G1494 - G1501. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. R. Partosoedarso, R. L. Young, and L. A. Blackshaw GABAB receptors on vagal afferent pathways: peripheral and central inhibition Am J Physiol Gastrointest Liver Physiol, April 1, 2001; 280(4): G658 - G668. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C.-S. Yuan, A. S. Attele, L. Dey, and J.-T. Xie Gastric Effects of Cholecystokinin and Its Interaction with Leptin on Brainstem Neuronal Activity in Neonatal Rats J. Pharmacol. Exp. Ther., October 1, 2000; 295(1): 177 - 182. [Abstract] [Full Text]
|
|
|
|
|
|
C.-S. Yuan, A. S. Attele, J. A. Wu, L. Zhang, and Z. Q. Shi Peripheral gastric leptin modulates brain stem neuronal activity in neonates Am J Physiol Gastrointest Liver Physiol, September 1, 1999; 277(3): G626 - G630. [Abstract] [Full Text] [PDF]
|
|
 |
 |
 |
|
 |
 |
 |
