Opioid receptors modulate recovery from consummatory successive negative contrast

Three experiments explored the role of the opioid system in consummatory successive negative contrast. In Experiment 1, rats treated with the nonspecific opioid-receptor antagonist naloxone (2 mg/kg) exhibited increased suppression after a shift from 32% to 6% sucrose solution (32 → 6), relative to...

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Detalles Bibliográficos
Autores: Pellegrini, Santiago, Wood, Michael, Daniel, Alan M., Papini, Mauricio Roberto
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/182067
Acceso en línea:http://hdl.handle.net/11336/182067
Access Level:acceso abierto
Palabra clave:CONSUMMATORY SUCCESSIVE NEGATIVE CONTRAST
NALOXONE
NALTRINDOLE
OPIOID RECEPTORS
https://purl.org/becyt/ford/5.1
https://purl.org/becyt/ford/5
Descripción
Sumario:Three experiments explored the role of the opioid system in consummatory successive negative contrast. In Experiment 1, rats treated with the nonspecific opioid-receptor antagonist naloxone (2 mg/kg) exhibited increased suppression after a shift from 32% to 6% sucrose solution (32 → 6), relative to 6 → 6 unshifted controls. A similar but shorter effect was observed with the delta-opioid receptor antagonist naltrindole (1 mg/kg). In Experiment 2, naloxone increased suppression after a more conventional 32 → 4 sucrose shift. In Experiment 3, rats classified as expressing slow recovery from contrast (after a 32 → 4 sucrose downshift) were more sensitive to naloxone in an activity test than fast-recovery rats. Whereas it was previously known that contrast was reduced by the extrinsic administration of opioid agonists, the effects reported here with antagonists provide the first evidence that the opioid system is intrinsically engaged by situations involving surprising reward loss.