Context and topography determine the role of basolateral amygdala metabotropic glutamate receptor 5 in appetitive Pavlovian responding
| Autor: | Ghislaine E. Deyab, Mandy Rita LeCocq, Shaun Yon-Seng Khoo, Nadia Chaudhri |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Male
Pyridines Receptor Metabotropic Glutamate 5 Conditioning Classical Context (language use) Fructose Nucleus accumbens Article 03 medical and health sciences 0302 clinical medicine Allosteric Regulation medicine Animals Rats Long-Evans Pharmacology Appetitive Behavior Metabotropic glutamate receptor 5 Chemistry Basolateral Nuclear Complex Glutamate receptor Classical conditioning Research Highlight 030227 psychiatry Behavior Addictive Thiazoles Psychiatry and Mental health Glucose medicine.anatomical_structure Metabotropic receptor MTEP Dizocilpine Maleate Excitatory Amino Acid Antagonists Neuroscience 030217 neurology & neurosurgery Basolateral amygdala Signal Transduction |
| Zdroj: | Neuropsychopharmacology |
| Popis: | Preclinical data have shown that the excitatory metabotropic Gα(q)-coupled glutamate receptor, mGluR5, has a role in substance abuse and relapse. However, little is known about the contribution of mGluR5 to the expression of conditioned responding elicited by appetitive Pavlovian cues. We investigated this question in rats that were trained to associate a discrete, auditory conditioned stimulus (CS) with a fructose-glucose solution (5.5% fructose/4.5% glucose; “sugar”). In subsequent tests for the expression of conditioned responding without sugar delivery, CS-elicited fluid port entries were elevated in a context associated with sugar, relative to an equally familiar, neutral context. Inhibiting mGluR5 via systemic injections of a negative allosteric modulator (MTEP; 5 mg/kg) reduced CS port entries in both the sugar context and neutral context. Targeting MTEP microinjections (3 µg/side; 0.3 µl/min) to the nucleus accumbens (Acb) core had no effect on CS port entries at test, whereas the same manipulation in the basolateral amygdala (BLA) produced effects that were topographically dependent. Specifically, microinjecting MTEP in the posterior BLA had no effect on behavior, whereas inhibiting mGluR5 in the anterior BLA enhanced the contextual discrimination of CS port entries. These data are the first to show a role of mGluR5 in the context-dependent expression of appetitive Pavlovian conditioned responding, with a topographically defined arrangement of mGluR5 in the BLA being particularly important for context-based responding to a discrete, appetitive cue. |
| Databáze: | OpenAIRE |
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