Home
Resources
Publications
M3 Muscarinic Receptor in the Ventral Medial Prefrontal Cortex Modulating the Expression of Contextual Fear Conditioning in Rats

M3 Muscarinic Receptor in the Ventral Medial Prefrontal Cortex Modulating the Expression of Contextual Fear Conditioning in Rats

A G Fedoce, N C Ferreira-Junior, D G Reis, F M A Corrêa, L B M Resstel

Psychopharmacology (Berl). 2016 Jan;233(2):267-80.

PMID: 26518024

Abstract:

Rationale:
Basal forebrain cholinergic neurons modulate the activation of cortical neurons by several stimuli such as fear and anxiety. However, the role of the muscarinic receptor in the medial prefrontal cortex (MPFC) in the modulation of the conditioned emotional response (CER) evoked in the model contextual conditioned fear remains unclear.
Objectives:
The objective of this study is to test the hypothesis that inhibition of the muscarinic receptor in ventral MPFC modulates CER observed during animal's re-exposure to the aversive context.
Methods:
Rats implanted with cannulae aimed at the prelimbic (PL) or the infralimbic (IL) were submitted to a high-intensity contextual fear conditioning protocol. Before the test session, they received microinjections of the hemicholinium (choline reuptake blocker), atropine (muscarinic antagonist), J104129 fumarate (M1-M3 muscarinic antagonists), pirenzepine (M1 muscarinic antagonist), neostigmine (inhibitor acetylcholinesterase enzyme), or the systemic administration of the FG7142 (inverse benzodiazepine agonist). Additional independent groups received the neostigmine or FG7142 before the ineffective doses of J104129 fumarate in the low-intensity protocol of contextual fear conditioning.
Results:
In the high-intensity protocol, the administration of hemicholinium (1 nmol), atropine (0.06-6 nmol), J104129 fumarate (6 nmol), or pirenzepine (6 nmol) attenuated the expression of CER in rats. However, in the low-intensity protocol, only J10129 fumarate (0.06 nmol) reduced the expression of the CER. Finally, neostigmine (0.1-1 nmol) or FG7142 (8 mg/Kg) increased CER expression, an effect inhibited by the low dose of the J10129 fumarate.
Conclusions:
These results indicated that the blockade of M3 muscarinic receptor in the vMPFC attenuates the CER expression.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP257603400	J104129 fumarate		257603-40-0	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: