VIRGOLINI MIRIAM BEATRIZ
Congresos y reuniones científicas
Título:
The NMDA antagonist MK-801 blocks stress-induced reinstatement in the conditioned place preference model
Autor/es:
2. DE GIOVANNI L., VIRGOLINI, M.B., CANCELA L.M.
Lugar:
Huerta Grande, Córdoba, Argentina
Reunión:
Congreso; I Reunión Conjunta de Neurociencias.; 2009
Institución organizadora:
Sociedad Argentina de Investigacion en Neurociencias
Resumen:
The NMDA antagonist MK-801 blocks stress-induced reinstatement in the conditioned place preference model
De Giovanni L., Virgolini, M.B., Cancela L.M.
IFEC-CONICET. Dpto de Farmacología, Facultad de Ciencias Químicas, UNC, Córdoba, Argentina. lcancela@fcq.unc.edu.ar
In previous results we have showed that using the conditioned place preference procedure, a single 30-min immobilization stress session induces the reinstatement of cocaine seeking behavior in animals previously conditioned with this drug. Moreover, we have also demonstrated that 72 hours after the reinstatement test, these animals reinstate again after a priming dose of cocaine. Based on recent research that suggests that the NMDA antagonist, MK 801, blocks cocaine-induced reinstatement, we aimed to prove that this blockade is also present after stress-induced reinstatement, providing at the same time further evidence for the shared neurobiological mechanisms between stress and cocaine. Male Wistar rats were injected with cocaine 10-mg/kg ip and confined to one of two compartments in four alternated daily sessions drug/vehicle; being the preference for each context later evaluated. The extinction phase consisted in successive associations with vehicle in both compartments. Reinstatement was evaluated measuring the time spent in each compartment after 30 min of immobilization stress and, 72 h later, in response to a cocaine priming injection (5 mg/kg). We demonstrated that a systemic injection of MK 801 (0.01 or 0.02 mg/kg) administered 15 minutes before the stress session, blocked stress-induced reinstatement and that this blockade persisted for at least 72 hours when was evaluated in response to a cocaine priming injection. These results support the hypothesis of a potential role of the NMDA receptor in the cocaine seeking behaviour induced by stress or cocaine. Further experiments are designed to identify the contribution of the reward and memory processes in the long-lasting MK-801 disruptive effects in addiction.
De Giovanni L., Virgolini, M.B., Cancela L.M.
IFEC-CONICET. Dpto de Farmacología, Facultad de Ciencias Químicas, UNC, Córdoba, Argentina. lcancela@fcq.unc.edu.ar
In previous results we have showed that using the conditioned place preference procedure, a single 30-min immobilization stress session induces the reinstatement of cocaine seeking behavior in animals previously conditioned with this drug. Moreover, we have also demonstrated that 72 hours after the reinstatement test, these animals reinstate again after a priming dose of cocaine. Based on recent research that suggests that the NMDA antagonist, MK 801, blocks cocaine-induced reinstatement, we aimed to prove that this blockade is also present after stress-induced reinstatement, providing at the same time further evidence for the shared neurobiological mechanisms between stress and cocaine. Male Wistar rats were injected with cocaine 10-mg/kg ip and confined to one of two compartments in four alternated daily sessions drug/vehicle; being the preference for each context later evaluated. The extinction phase consisted in successive associations with vehicle in both compartments. Reinstatement was evaluated measuring the time spent in each compartment after 30 min of immobilization stress and, 72 h later, in response to a cocaine priming injection (5 mg/kg). We demonstrated that a systemic injection of MK 801 (0.01 or 0.02 mg/kg) administered 15 minutes before the stress session, blocked stress-induced reinstatement and that this blockade persisted for at least 72 hours when was evaluated in response to a cocaine priming injection. These results support the hypothesis of a potential role of the NMDA receptor in the cocaine seeking behaviour induced by stress or cocaine. Further experiments are designed to identify the contribution of the reward and memory processes in the long-lasting MK-801 disruptive effects in addiction.
