Novel presynaptic mechanisms for coincidence detection in synaptic plasticity.
Long-term plasticity typically relies on postsynaptic NMDA receptors to detect the coincidence of pre- and postsynaptic activity. Recent studies, however, have revealed forms of plasticity that depend on coincidence detection by presynaptic NMDA receptors. In the amygdala, cortical afferent associative presynaptic long-term potentiation (LTP) requires activation of presynaptic NMDA receptors by simultaneous thalamic and cortical afferents. Surprisingly, both types of afferent can also undergo postsynaptically induced NMDA-receptor-dependent LTP. In the neocortex, spike-timing-dependent long-term depression (LTD) requires simultaneous activation of presynaptic NMDA autoreceptors and retrograde signalling by endocannabinoids. In cerebellar LTD, presynaptic NMDA receptor activation suggests that similar presynaptic mechanisms may exist. Recent studies also indicate the existence of presynaptic coincidence detection that is independent of NMDA receptors, suggesting that such mechanisms have a widespread role in plasticity.
Duguid
Ian
I
Wolfson Institute for Biomedical Research and Department of Physiology, University College London, Gower Street, London WC1E 6BT, UK.
Sjöström
Per Jesper
PJ
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D017774:Long-Term Potentiation / Q000502:physiology; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology*; D017729:Presynaptic Terminals / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology*; D013997:Time Factors
D016194:Receptors, N-Methyl-D-Aspartate