J Physiol Editor in Chief
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Physiology in Press

First published online on May 9, 2003.
 Copyright © 2003 by The Physiological Society
This Article
Right arrow Full Text (Rapid PDF)
Right arrow All Versions of this Article:
550/1/181    most recent
2003.043273v1
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 Teramoto, N.
Right arrow Articles by Hirst, G. D. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Teramoto, N.
Right arrow Articles by Hirst, G. D. S.

Received March 18, 2003
Accepted after revision April 11, 2003

Interaction between excitatory and inhibitory metabotropic pathways in the guinea-pig antrum

N. Teramoto1 and G. D. S. Hirst2*

1 Department of Pharmacology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
2 Department of Zoology, University of Melbourne, Victoria, 3010, Australia

* To whom correspondence should be addressed. E-mail: d.hirst{at}zoology.unimelb.edu.au.

Intracellular recordings were made from isolated bundles of the circular muscle layer of guinea-pig gastric antrum and the responses evoked by stimulating nitrergic nerve fibres were examined. Nitrergic inhibitory junction potentials (nitrergic-IJPs), evoked by trains of stimuli, had small amplitudes and were associated with a reduction in the rate of occurrence and amplitude of spontaneously occurring depolarizing potentials, termed unitary potentials. Nitrergic-IJPs were abolished either by membrane hyperpolarization or by 4,4â-diisothiocyano-2,2â-stilbene disulfonic acid (DIDS); both of these abolished the discharge of unitary potentials. Membrane depolarization increased the rate of discharge of unitary potentials so that they summed to give rise to a regenerative potential. Nitrergic nerve stimulation abolished regenerative potentials; this inhibition did not result from a change in threshold for the initiation of regenerative potentials, rather it occurred at some stage after the gating process. Inhibitory nitrergic nerve responses were blocked by L-nitroarginine (NOLA) and oxadiazolo quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase. The observations suggest that the inhibition of regenerative potentials results from an interaction between an inhibitory and an excitatory metabotropic pathway.




This article has been cited by other articles:


Home page
 J. Physiol.Home page
S. J. Hwang, N. O'Kane, C. Singer, S. M. Ward, K. M. Sanders, and S. D. Koh
Block of inhibitory junction potentials and TREK-1 channels in murine colon by Ca2+ store-active drugs
J. Physiol., February 15, 2008; 586(4): 1169 - 1184.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
Y. Takeda, S. D. Koh, K. M. Sanders, and S. M. Ward
Differential expression of ionic conductances in interstitial cells of Cajal in the murine gastric antrum
J. Physiol., February 1, 2008; 586(3): 859 - 873.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
E. A. H. Beckett, Y. R. Bayguinov, K. M. Sanders, S. M. Ward, and G. D. S. Hirst
Properties of unitary potentials generated by intramuscular interstitial cells of Cajal in the murine and guinea-pig gastric fundus
J. Physiol., August 15, 2004; 559(1): 259 - 269.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
G. D. S. Hirst, R. A. R. Bywater, N. Teramoto, and F. R. Edwards
An analysis of inhibitory junction potentials in the guinea-pig proximal colon
J. Physiol., August 1, 2004; 558(3): 841 - 855.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Copyright © 2003 The Physiological Society.