Is activation of N-methyl-D-aspartate receptor gated channels sufficient to induce long term potentiation?
Superfusion of hippocampal slices with Mg2+ free medium (20-30 min) produced in CA1 interictal bursts and an enhancement of the Schaffer collateral synaptic response which persisted for over 2 h after return to control media. This long lasting effect, which was blocked by N-methyl-D-aspartate (NMDA) antagonists, was not associated with changes in postsynaptic cell excitability. A cut between CA3 and CA1, which blocked the bursts in CA1 (but not in CA3), also abolished the long lasting effects of Mg2+ free medium. It is concluded that the activation of NMDA receptors gated ionic channels is insufficient per se to induce a long term potentiation of synaptic transmission.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000502:physiology; D004558:Electric Stimulation; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects / Q000502:physiology*; D008274:Magnesium / Q000502:physiology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D016202:N-Methylaspartate; D051381:Rats; D011919:Rats, Inbred Strains; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000502:physiology*
D007473:Ion Channels; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D001224:Aspartic Acid; D016202:N-Methylaspartate; D008274:Magnesium