Spatial learning and goldfish telencephalon NMDA receptors.
Recent results have demonstrated that the mammalian hippocampus and the dorso-lateral telencephalon of ray-finned fishes share functional similarities in relation to spatial memory systems. In the present study, we investigated whether the physiological mechanisms of this hippocampus-dependent spatial memory system were also similar in mammals and ray-finned fishes, and therefore possibly conserved through evolution in vertebrates. In Experiment 1, we studied the effects of the intracranial administration of the noncompetitive NMDA receptor antagonist MK-801 during the acquisition of a spatial task. The results indicated dose-dependent drug-induced impairment of spatial memory. Experiment 2 evaluated if the MK-801 produced disruption of retrieval of a learned spatial response. Data showed that the administration of MK-801 did not impair the retrieval of the information previously stored. The last experiment analyzed the involvement of the telencephalic NMDA receptors in a spatial and in a cue task. Results showed a clear impairment in spatial learning but not in cue learning when NMDA receptors were blocked. As a whole, these results indicate that physiological mechanisms of this hippocampus-dependent system could be a general feature in vertebrate, and therefore phylogenetically conserved.
Gómez
Yolanda
Y
Laboratorio de Neurociencia de la Conducta, Departamento de Psicología Experimental, Facultad de Psicología, Campus Ramón y Cajal, C/Camilo José Cela s/n, 41018 Sevilla, Spain.
Vargas
Juan Pedro
JP
Portavella
Manuel
M
López
Juan Carlos
JC
D000818:Animals; D005075:Biological Evolution; D016291:Dizocilpine Maleate / Q000008:administration & dosage / Q000494:pharmacology; D006054:Goldfish; D006624:Hippocampus / Q000187:drug effects; D007858:Learning / Q000187:drug effects*; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000494:pharmacology; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D013028:Space Perception / Q000187:drug effects*; D013687:Telencephalon / Q000187:drug effects*
D018696:Neuroprotective Agents; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate