NMDA receptor subunits change following synaptic plasticity induction and memory acquisition

MAGALI C. CERCATO; DIANA A. JERUSALINSKY; MARIA V. BAEZ

Neural Plasticity

Hindawi

Año: 2018 vol. 2018

NMDA (N-methyl-D-aspartate) glutamate receptors (NMDARs) are crucial in activity dependent synaptic changes, and in learning and memory. NMDARs are composed of two GluN1 essential subunits and two regulatory subunits that defines its physiological profile. In CNS structures involved in cognitive functions, like hippocampus and prefrontal cortex, GluN2A and GluN2B are the major regulatory subunits; their expression is dynamic and tightly regulated. However, little is known about specific changes after plasticity induction or memory acquisition. Changes in GluN1 -or NMDARs- induced by synaptic plasticity and by spatial memory formation seem to occur in different transport/expression/degradation waves, with a net increase at the postsynaptic side and a rise in expression at both dendritic spines and neuronal soma. Data strongly suggest that following appropriate stimulation, there is a rapid surface increase of GluN2A-NMDAR at the postsynaptic side, attributed to lateral mobilization from adjacent locations. Whenever synaptic plasticity is induced or memory is consolidated, more GluN2A-NMDARs are assembled likely using GluN2A locally translated and GluN1 locally stored at the endoplasmic reticulum. Later on, subunits would be mobilized from other pools that should be refilled by de novo synthesis at the neuronal soma. This review aims to put together that information and the proposed hypotheses