Please use this identifier to cite or link to this item:
https://hdl.handle.net/2440/133569
Citations | ||
Scopus | Web of Science® | Altmetric |
---|---|---|
?
|
?
|
Type: | Journal article |
Title: | Peristalsis and propulsion of colonic content can occur after blockade of major neuroneuronal and neuromuscular transmitters in isolated guinea pig colon |
Author: | Sia, T.C. Brookes, S.J. Dinning, P.G. Wattchow, D.A. Spencer, N.J. |
Citation: | American Journal of Physiology: Gastrointestinal and Liver Physiology, 2013; 305(12):G933-G939 |
Publisher: | American Physiological Society |
Issue Date: | 2013 |
ISSN: | 0193-1857 1522-1547 |
Statement of Responsibility: | T. C. Sia, S. J. Brookes, P. G. Dinning, D. A. Wattchow and N. J. Spencer |
Abstract: | We recently identified hexamethonium-resistant peristalsis in the guinea pig colon. We showed that, following acute blockade of nicotinic receptors, peristalsis recovers, leading to normal propagation velocities of fecal pellets along the colon. This raises the fundamental question: what mechanisms underlie hexamethonium-resistant peristalsis? We investigated whether blockade of the major receptors that underlie excitatory neuromuscular transmission is required for hexamethonium-resistant peristalsis. Video imaging of colonic wall movements was used to make spatiotemporal maps and determine the velocity of peristalsis. Propagation of artificial fecal pellets in the guinea pig distal colon was studied in hexamethonium, atropine, ω-conotoxin (GVIA), ibodutant (MEN-15596), and TTX. Hexamethonium and ibodutant alone did not retard peristalsis. In contrast, ω-conotoxin abolished peristalsis in some preparations and reduced the velocity of propagation in all remaining specimens. Peristalsis could still occur in some animals in the presence of hexamethonium + atropine + ibodutant + ω-conotoxin. Peristalsis never occurred in the presence of TTX. The major finding of the current study is the unexpected observation that peristalsis can occur after blockade of the major excitatory neuroneuronal and neuromuscular transmitters. Also, the colon retained an intrinsic polarity in the presence of these antagonists and was only able to expel pellets in an aboral direction. The nature of the mechanism(s)/neurotransmitter(s) that generate(s) peristalsis and facilitate(s) natural fecal pellet propulsion, after blockade of major excitatory neurotransmitters, at the neuroneuronal and neuromuscular junction remains to be identified. |
Keywords: | Peristalsis, hexamethonium resistance, colon; acetylcholine; ω-conotoxin (GVIA), ibodutant; nicotinic; muscarinic |
Rights: | © 2013 the American Physiological Society |
DOI: | 10.1152/ajpgi.00257.2013 |
Grant ID: | http://purl.org/au-research/grants/nhmrc/10257566 |
Published version: | http://dx.doi.org/10.1152/ajpgi.00257.2013 |
Appears in Collections: | Medicine publications |
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.