Synaptic plasticity: LTP and LTD.
Long-term potentiation (LTP) is a synaptic enhancement that follows brief, high-frequency electrical stimulation in the hippocampus and neocortex. Recent evidence suggests that induction of LTP may require, in addition to postsynaptic Ca2+ entry, activation of metabotropic glutamate receptors and the generation of diffusible intercellular messengers. A new form of synaptic plasticity, homosynaptic long-term depression (LTD) has also recently been documented, which, like LTP, requires Ca2+ entry through the NMDA receptor. Current work suggests that this LTD is a reversal of LTP, and vice versa, and that the mechanisms of LTP and LTD may converge at the level of specific phosphoproteins.
Bear
M F
MF
Department of Neuroscience, Brown University, Providence, Rhode Island 02912.
Malenka
R C
RC
D000818:Animals; D006801:Humans; D017774:Long-Term Potentiation; D009473:Neuronal Plasticity; D018094:Receptors, Metabotropic Glutamate / Q000502:physiology; D015290:Second Messenger Systems; D013569:Synapses / Q000502:physiology*
D018094:Receptors, Metabotropic Glutamate