Double dissociation of hippocampal and dorsal-striatal memory systems by posttraining intracerebral injections of 2-amino-5-phosphonopentanoic acid.
Rats received an 8-trial training session on a spatial or cued task in a water maze, followed by a posttraining intracerebral injection of AP5 or saline. On a retention test 24 hr later, latency to mount the escape platform was used as a measure of memory. Intrahippocampal (10 micrograms), but not intra-dorsal striatal (2, 5, or 10 micrograms), injection of AP5 impaired memory in the spatial task. In contrast, intra-dorsal striatal (2 micrograms), but not intrahippocampal (2, 5, or 10 micrograms) injection of AP5 impaired memory in the cued task. Intracerebral injections of AP5 delayed 2 hr posttraining were ineffective. The findings indicate a double dissociation of the roles of the hippocampus and dorsal striatum in memory, a role for N-methyl-D-aspartate receptor function in posttraining memory processes, and a glutamatergic modulation of both hippocampal and dorsal striatal memory processes, suggesting that different forms of memory may share a similar neurochemical basis.
Packard
M G
MG
Department of Psychology, University of New Orleans, Louisiana 70148, USA. mgpps@uno.edu
Teather
L A
LA
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology*; D000818:Animals; D001931:Brain Mapping; D003342:Corpus Striatum / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004924:Escape Reaction / Q000187:drug effects* / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D008297:Male; D018782:Maze Learning / Q000187:drug effects* / Q000502:physiology; D011939:Mental Recall / Q000187:drug effects / Q000502:physiology; D009949:Orientation / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000502:physiology; D012153:Retention, Psychology / Q000187:drug effects* / Q000502:physiology
D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D015763:2-Amino-5-phosphonovalerate