Latent inhibition disruption by MK-801 in a conditioned taste-aversion paradigm.
N-Methyl-D-aspartate (NMDA) receptors appear to be involved in CS processing and memory consolidation. The present paper analyzed the effect of the non-competitive NMDA receptor antagonist Dizocilpine maleate (MK-801) on Latent Inhibition (LI)-retarded learning of a CS-US association after to-be-CS preexposures at time of testing, using Wistar rats as experimental subjects. If NMDA receptors are involved in CS processing, MK-801 administration should affect LI. In fact, previous experiments revealed that a 2.0mg/kg MK-801 dose, administered 20 h before preexposure and conditioning, abolished LI in a conditioned taste-aversion paradigm. In the present paper, MK-801 (0.2 mg/kg) was either injected after preexposure, after conditioning, or after both preexposure and conditioning stages. LI was abolished when MK-801 was injected after preexposure, but not when it was injected after conditioning. These results support the role of NMDA receptors in CS processing and memory consolidation.
Traverso
L M
LM
Facultad de Psicologia, University of Seville, C/Camilo Jose Cela, s/n, 41018 Sevilla, Spain.
Ruiz
G
G
De la Casa
L G
LG
D000818:Animals; D003213:Conditioning, Psychological / Q000502:physiology*; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D007266:Inhibition, Psychological; D008297:Male; D008568:Memory / Q000187:drug effects; D018696:Neuroprotective Agents / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013649:Taste / Q000187:drug effects*
D018696:Neuroprotective Agents; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate