Cholinergic, but not NMDA, receptors in the lateral entorhinal cortex mediate acquisition in trace eyeblink conditioning

© 2015 Wiley Periodicals, Inc..

Anatomical and electrophysiological studies collectively suggest that the entorhinal cortex consists of several subregions, each of which is involved in the processing of different types of information. Consistent with this idea, we previously reported that the dorsolateral portion of the entorhinal cortex (DLE), but not the caudomedial portion, is necessary for the expression of a memory association between temporally discontiguous stimuli in trace eyeblink conditioning (Morrissey et al. (2012) J Neurosci 32:5356-5361). The present study examined whether memory acquisition depends on the DLE and what types of local neurotransmitter mechanisms are involved in memory acquisition and expression. Male Long-Evans rats experienced trace eyeblink conditioning, in which an auditory conditioned stimulus (CS) was paired with a mildly aversive electric shock to the eyelid (US) with a stimulus-free interval of 500 ms. Immediately before the conditioning, the rats received a microinfusion of neuroreactive substances into the DLE. We found that reversible inactivation of the DLE with GABAA receptor agonist, muscimol impaired memory acquisition. Furthermore, blockade of local muscarinic acetylcholine receptors (mACh) with scopolamine retarded memory acquisition while blockade of local NMDA receptors with APV had no effect. Memory expression was not impaired by either type of receptor blocker. These results suggest that the DLE is necessary for memory acquisition, and that acquisition depends on the integrity of local mACh receptor-dependent firing modulation, but not NMDA receptor-dependent synaptic plasticity.

Medienart:

E-Artikel

Erscheinungsjahr:

2015

Erschienen:

2015

Enthalten in:

Zur Gesamtaufnahme - volume:25

Enthalten in:

Hippocampus - 25(2015), 11 vom: 08. Nov., Seite 1456-64

Sprache:

Englisch

Beteiligte Personen:

Tanninen, Stephanie E [VerfasserIn]
Yu, XiaoTian [VerfasserIn]
Giritharan, Thamy [VerfasserIn]
Tran, Lina [VerfasserIn]
Bakir, Rami [VerfasserIn]
Volle, Julien [VerfasserIn]
Morrissey, Mark D [VerfasserIn]
Takehara-Nishiuchi, Kaori [VerfasserIn]

Links:

Volltext

Themen:

2763-96-4
DL48G20X8X
Entorhinal cortex
Eyeblink conditioning
GABA-A Receptor Agonists
Journal Article
Muscarinic Antagonists
Muscimol
Rats
Receptors, Cholinergic
Receptors, N-Methyl-D-Aspartate
Research Support, Non-U.S. Gov't
Reversible inactivation
Scopolamine
Trace conditioning

Anmerkungen:

Date Completed 29.08.2016

Date Revised 02.12.2018

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1002/hipo.22466

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM247965146