-
Neuroscience letters · Oct 2013
Contribution of muscarinic M1 receptors to the cholinergic suppression of synaptic responses in layer II of the entorhinal cortex.
- Shawnna G Barrett and C Andrew Chapman.
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, Québec, Canada H4B 1R6.
- Neurosci. Lett. 2013 Oct 25; 554: 11-5.
AbstractThe entorhinal cortex is thought to play roles in sensory and mnemonic function, and the cholinergic suppression of the strength of synaptic inputs is likely to have important impacts on these processes. Field excitatory postsynaptic potentials (fEPSPs) in the medial entorhinal cortex evoked by stimulation of the piriform cortex are suppressed during theta EEG activity in behaving animals, and cholinergic receptor activation suppresses synaptic responses both in vivo, and in layer II entorhinal neurons in vitro. Here, we have used in vitro field potential recordings to investigate the transmitter receptors that mediate the cholinergic suppression of synaptic responses in layer I inputs to layer II of the medial entorhinal cortex. Bath-application of the cholinergic agonist carbachol suppressed the amplitude of fEPSPs with an EC50 of 5.3μM, and enhanced paired-pulse ratio. The M2/M4 preferring receptor blocker methoctramine, or the M4 receptor blocker PD102807, did not prevent the cholinergic suppression. However, the M1/M4 receptor blocker pirenzepine and the M1 receptor blocker VU0255035 reduced the suppression, suggesting that the cholinergic suppression of synaptic responses in the entorhinal cortex is dependent in large part on activation of M1 receptors.Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Notes
Knowledge, pearl, summary or comment to share?You can also include formatting, links, images and footnotes in your notes
- Simple formatting can be added to notes, such as
*italics*
,_underline_
or**bold**
. - Superscript can be denoted by
<sup>text</sup>
and subscript<sub>text</sub>
. - Numbered or bulleted lists can be created using either numbered lines
1. 2. 3.
, hyphens-
or asterisks*
. - Links can be included with:
[my link to pubmed](http://pubmed.com)
- Images can be included with:
![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
- For footnotes use
[^1](This is a footnote.)
inline. - Or use an inline reference
[^1]
to refer to a longer footnote elseweher in the document[^1]: This is a long footnote.
.