Place-cell impairment in glutamate receptor 2 mutant mice.
There is a strong correlation between Hebbian, NMDA receptor-dependent long-term potentiation (LTP), place-cell firing, and learning and memory. We made glutamate receptor 2 (GluR2) null mutant mice that show enhanced non-Hebbian LTP in hippocampal CA1 neurons and impaired performance in a spatial learning task. We concluded that in vivo hippocampal place cells of GluR2 mutant mice were functionally impaired because (1) only 22.6% of CA1 neurons showed place fields in GluR2 mutant mice, which was significantly lower than that (43.8%) in wild-type mice; (2) GluR2 mutant place fields were much less precise; and (3) GluR2 mutant place fields were extremely unstable. Our data suggest that place cells of GluR2 knock-out mice did not form robust place fields, and that enhanced non-Hebbian LTP might play a negative role in their formation.
Yan
Jun
J
Department of Physiology and Biophysics, University of Calgary, Calgary, T2N 4NI Canada.
Zhang
Yunfeng
Y
Jia
Zhenping
Z
Taverna
Franco A
FA
McDonald
Robert J
RJ
Muller
Robert U
RU
Roder
John C
JC
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D004567:Electrodes, Implanted; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D007858:Learning / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology*; D008568:Memory / Q000502:physiology; D051379:Mice; D008817:Mice, Mutant Strains; D017966:Pyramidal Cells / Q000502:physiology*; D018091:Receptors, AMPA / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D013037:Spatial Behavior / Q000502:physiology
D018091:Receptors, AMPA; C104722:glutamate receptor ionotropic, AMPA 2