ABSTRACT
Information storage in the brain involves alterations in the strength of communication between neurons. This requires activity-dependent, long-lasting changes in synaptic transmission. Long-term potentiation (LTP) is a long lasting use-dependent increase
in the efficiency of excitatory synaptic transmission that has been suggested to underlie certain forms of learning and memory [1]. The induction of LTP requires Ca
entry through the N-methyl-D-aspartate receptor (NMDAR). However, the region within the synapse whose regulation results in LTP is still controversial. Some groups suggest a pre-synaptic modification that results in an increase in the amount of glutamate released, whereas others suggest a post-synaptic modification, such as an increase in the number of receptors or a change in receptor properties [2]. Interestingly, the description of the silent synapse, synapses that contain NMDAR only but could acquire
α
-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) as a result of synaptic activity, support a post-synaptic mechanism [3-5].
