title: A juvenile form of postsynaptic hippocampal long-term potentiation in mice deficient for the AMPA receptor subunit GluR-A.
abstract: In adult mice, long-term potentiation (LTP) of synaptic transmission at CA3-to-CA1 synapses induced by tetanic stimulation requires L-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors containing GluR-A subunits. Here, we report a GluR-A-independent form of LTP, which is comparable in size to LTP in wild-type mice at postnatal day 14 (P14) but diminishes between P14 and P42 in brain slices of GluR-A-deficient mice. The GluR-A-independent form of LTP is sensitive to D(-)-2-amino-5-phosphonopentanoic acid (D-AP5), but lacks short-term potentiation (STP) and can also be observed in the pairing induction protocol. As judged by unaltered paired-pulse facilitation, this LTP form is postsynaptically expressed despite depleted extrasynaptic AMPA receptor pools with reduced levels of GluR-B, which accumulates in somata and synapses of CA1 pyramidal neurons in GluR-A-deficient mice. Our results show that in the developing hippocampus synaptic plasticity can be expressed by AMPA receptors lacking the GluR-A subunit.
authors.affiliation: Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, PO Box 1103 Blindern, N0317 Oslo, Norway.
authors.forename: Vidar
authors.initials: V
authors.lastname: Jensen
authors.forename: Katharina M M
authors.initials: KM
authors.lastname: Kaiser
authors.forename: Thilo
authors.initials: T
authors.lastname: Borchardt
authors.forename: Giselind
authors.initials: G
authors.lastname: Adelmann
authors.forename: Andrei
authors.initials: A
authors.lastname: Rozov
authors.forename: Nail
authors.initials: N
authors.lastname: Burnashev
authors.forename: Christian
authors.initials: C
authors.lastname: Brix
authors.forename: Michael
authors.initials: M
authors.lastname: Frotscher
authors.forename: Per
authors.initials: P
authors.lastname: Andersen
authors.forename: Øivind
authors.initials: Ø
authors.lastname: Hvalby
authors.forename: Bert
authors.initials: B
authors.lastname: Sakmann
authors.forename: Peter H
authors.initials: PH
authors.lastname: Seeburg
authors.forename: Rolf
authors.initials: R
authors.lastname: Sprengel
mesh_terms: D000818:Animals; D001483:Base Sequence; D003433:Crosses, Genetic; D017931:DNA Primers; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016253:Microscopy, Immunoelectron; D021122:Protein Subunits / Q000235:genetics; D017966:Pyramidal Cells / Q000502:physiology; D018091:Receptors, AMPA / Q000172:deficiency* / Q000235:genetics / Q000502:physiology*; D012016:Reference Values; D009435:Synaptic Transmission
chemical_list: D017931:DNA Primers; D021122:Protein Subunits; D018091:Receptors, AMPA