Referenced in: none

Automatically associated channels: Slo1

Title: Presynaptic induction and expression of timing-dependent long-term depression demonstrated by compartment-specific photorelease of a use-dependent NMDA receptor antagonist.

Authors: Antonio Rodríguez-Moreno, Michael M Kohl, James E Reeve, Thomas R Eaton, Hazel A Collins, Harry L Anderson, Ole Paulsen

Journal, date & volume: J. Neurosci., 2011 Jun 8 , 31, 8564-9

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/21653860

Abstract
NMDA receptors are important for synaptic plasticity, including long-term potentiation (LTP) and long-term depression (LTD). To help investigate the precise location of the NMDA receptors that are required for different types of synaptic plasticity, we synthesized a caged form of the use-dependent NMDA receptor antagonist MK801, which we loaded into individual neurons in vitro, followed by compartment-specific uncaging. We used this method to investigate timing-dependent plasticity at layer 4-layer 2/3 synapses of mouse barrel cortex. Somatodendritic photorelease of MK801 in the postsynaptic neuron produced a use-dependent block of synaptic NMDA receptor-mediated currents and prevented the induction of LTP. Compartment-specific photorelease of MK801 in the presynaptic neuron showed that axonal, but not somatodendritic, presynaptic NMDA receptors are required for induction of LTD. The rate of use-dependent block of postsynaptic NMDA receptor current was slower following induction of LTD, consistent with a presynaptic locus of expression. Thus, this new caged compound has demonstrated the axonal location of NMDA receptors required for induction and the presynaptic locus of expression of LTD at layer 4-layer 2/3 synapses.