Please use this identifier to cite or link to this item:
https://hdl.handle.net/2440/47323
Citations | ||
Scopus | Web of Science® | Altmetric |
---|---|---|
?
|
?
|
Type: | Journal article |
Title: | Loss of enteric motor neurotransmission in the gastric fundus of Sl/Sld mice |
Author: | Spencer, E. Horiguchi, K. Khoyi, M. Sanders, K. Ward, S. |
Citation: | The Journal of Physiology, 2002; 543(3):871-887 |
Publisher: | Blackwell Publishing Ltd |
Issue Date: | 2002 |
ISSN: | 0022-3751 1469-7793 |
Statement of Responsibility: | Elizabeth A. H. Beckett, Kazuhide Horiguchi, Mohammad Khoyi, Kenton M. Sanders and Sean M. Ward |
Abstract: | Studies of W/WV mice, which lack intramuscular interstitial cells of Cajal (IC-IM), have suggested that IC-IM act as mediators of enteric motor neurotransmission in the gastrointestinal tract. We have studied Sl/Sld mice, which lack the ability to make membrane-bound stem cell factor, to determine the consequences of inappropriate stem cell factor expression on IC-IM populations and on enteric motor neurotransmission. IC-IM were found within the circular and longitudinal muscles of the gastric fundus of wild-type mice. IC-IM were intimately associated with motor nerve terminals and nerve varicosities formed synaptic structures with these cells. IC-IM were also connected with neighbouring smooth muscle cells via gap junctions. Immunohistochemistry and electron microscopy showed that IC-IM were absent from fundus muscles of Sl/Sld mice, but the density of excitatory and inhibitory nerves was not significantly different than in wild-type muscles. Loss of IC-IM was associated with decreased membrane noise (unitary potentials) and significant reductions in post-junctional excitatory and inhibitory enteric nerve responses. Reductions in neural responses were not due to defects in smooth muscle cells as responses to exogenous ACh and K+-induced depolarization were normal in Sl/Sld mice. Responses to neurally released ACh were revealed in Sl/Sld mice by inhibiting ACh breakdown with the acetylcholinesterase inhibitor neostigmine. Inhibitory nerve stimulation elicited inhibitory junction potentials (IJPs) and relaxations in wild-type mice. IJPs were reduced in amplitude and relaxation responses were absent in Sl/Sld mice. These observations suggest that membrane-bound stem cell factor is essential for development of IC-IM and that the close, synaptic-like relationship between nerve terminals and IC-IM may be the primary site of innervation by enteric motor neurons in gastric muscles. |
Keywords: | Muscle, Smooth Gastric Fundus Motor Neurons Enteric Nervous System Animals Mice Mice, Mutant Strains Nitroprusside Neostigmine Acetylcholine Cholinesterase Inhibitors Vasodilator Agents Microscopy, Electron Artifacts Electric Stimulation Synaptic Transmission Excitatory Postsynaptic Potentials Muscle Tonus |
Description: | Copyright © 2002 The Physiological Society |
DOI: | 10.1113/jphysiol.2002.021915 |
Published version: | http://jp.physoc.org/cgi/reprint/543/3/871 |
Appears in Collections: | Aurora harvest Molecular and Biomedical Science 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.