The microinjection of AMPA receptor antagonist into the accumbens shell failed to change food intake, but reduced fear-motivated behaviour in free-feeding female rats.
This study investigated the effect of the AMPA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 2.5 and 5.0 nmol/side) microinjected into the core and shell sub-regions of the accumbens (Acb) nucleus, on food intake and the level of anxiety in female rats. Bilateral microinjections of CNQX (5.0 nmol/side) into the Acb shell (AP, +1.08 to +2.04), but not into the Acb core, induced an anxiolytic-like effect in relation to rats microinjected with vehicle, since the animals exhibited low level of SAP in the feeding test. The anxiolytic-like effect induced by 5.0 nmol CNQX microinjection into the Acb shell may not be ascribed to changes in the motor activity of the animals, because the frequency of locomotion, rearing and grooming remained unchanged after the drug microinjection. However, neither Acb shell nor Acb core CNQX microinjections were able to change the animals food intake along 1h feeding behaviour evaluation. Food intake remained unchanged 24h after the drug microinjections either into the Acb shell or into the Acb core. The data suggest that AMPA receptor blockade in the Acb nucleus may differentially change the ingestive and defensive behaviours in female rats.
da Cunha
Isabel Cristina
IC
Department of Physiological Sciences, Centre of Biological Sciences, Federal University of Santa Catarina (UFSC), Campus Trindade, 88.040-900 Florianópolis, SC, Brazil.
de Nazareth
Aparecida Marcelino
AM
Vargas
Juliano Cordova
JC
Ferraz
Adriana
A
Neto
José Marino
JM
Paschoalini
Marta Aparecida
MA
Faria
Moacir Serralvo
MS
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000008:administration & dosage / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D001007:Anxiety / Q000503:physiopathology / Q000523:psychology; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects* / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D005106:Exploratory Behavior / Q000187:drug effects / Q000502:physiology; D005239:Fear / Q000523:psychology; D005260:Female; D005518:Food Preferences / Q000187:drug effects / Q000502:physiology; D006120:Grooming / Q000187:drug effects / Q000502:physiology; D008845:Microinjections; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors*; D013997:Time Factors
D018691:Excitatory Amino Acid Antagonists; D018091:Receptors, AMPA; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione